How do I solve this equation?
399448
log(3x+7) = 0\n10^0 = 3x+7\n1 = 3x+7\n-6 = 3x\nx = -2
915753
To help solve for t you'll need to use the quadratic formula. It's too difficult to show how I got the answer since I can't use the correct symbols, but the answer is t = 1.39.
518727
Multiply the first equation by 2.\n\nSubtract the second equation from the new first equation.\n\nSolve for y.\n\nTake your value for y and substitute it into the original first equation.\n\nSolve for x.
986332
y=ln[sec5x+tan5x]\ny'={1/[sec5x+tan5x]}[5sec5xtan5x+5sec^25x]\n=5sec5x[sec5x+tan5x]/[sec5x+tan5x]\n=5sec5x
255958
Substitute 2 for x and solve for c.\n2^2-3(2)+c=0\nRemember do powers, then multiplication, then subtraction.
831674
1. replace x with -3, calculate and see if you get 0\n2. divide by (x+3) and solve the remaining quadratic equation
289077
add all the equations, you get\n2(r+s+t) = 56\nso,\nr+s+t = 56/2 = 28\ndone!!
829854
Use logarithms to bring exponents down where you can deal with them.  Since the natural log is base e, that's the way to go here.\n\ne^5x = 7\n\n5x = ln 7\n\nand solve from there.
122445
Just replace x with -3 and y with 4 in each equation and then solve for the remaining variable.\n5x + 7y = b\n5(-3) + 7(4) = b\n-15 + 28 = b\nb = 13\n\nmx + y = 22\nm(-3) + 4 = 22  Subtract 4 from both sides\n-3m = 18  Divide both sides by -3\nm = 18/-3\nm = -6
212357
As I am sure you soon realized, this is a bit challenging. You cannot solve it easily by algebra, although you can make a series expansion approximation of ln y, or exp(y) and approximate the answer to this kind of equation in some cases. \n\nA more general approach is apply some numerical technique, like the Newton-Raphson method. \n\nLet F(Y)=ln(Y) + 10Y -4\n\nYou want to find the roots of F(Y), i.e., those values Y* such that F(Y*)=0. \n\nSet up an iteration Yn+1 = Yn - F(Yn) / F'(Yn)\n\n\n\nwhere the derivative F'(Y)= (1/Y)+10. \n\nTry it and see if it converges for you.
811856
Okay multiply the top equation by 7 and the bottom equation by negative 3 to obtain 2 new equations with the x variable to eliminate:\n\n7(3x + 7y = -43)\n-3(7x + 6y = -59)\n\nthis becomes \n\n21x + 49y = -301\n-21x - 18y = 177\n\nNow cancel out the 21x's and add down.  Doing that, the equation becomes\n\n31y = -124   this can easily be solved for y\n\ny = -4\n\nNow plug -4 back into one of the original equations\n\n3x + 7(-4) = -43\n\n3x - 28 = -43\n\nadd 28 to both sides to yield\n\n3x = -15   and solve for x\n\nx = -5\n\nNow check x = -5 and y = -4 into both and see that you have solved this system correctly.
224079
try this site... it shows step by step how to go about sloving these equations, good luck:
728397
You need to first balance the equation.\n\n2CO + O2 --> 2CO2\n\nUsing this you find the answer to be D.
765649
switch the variables.\n\nStart with\n\ny = sin(0.5x-3)\n\nand solve for x.\n\nto get rid of  the sin, we apply arcsin or sin^-1 (on calculators)\n\narcsin(y) = arcsin(sin(.5x - 3))\n\nthis gives\n\narcsin(y) = .5x - 3\n\nx = 2*[arcsin(y) + 3]
937830
T=m1*-9.8+m1*a\nT=m2*a--m2*-9.8\n\nset them equal and solve for a\n\ntrust me, i had a test on this today
697874
Multiply or divide all components in one question to set the variables in the opposite questions to cancel out if you added the two problems together by combining like terms. For example:\n2x + 3y = -13  and 4x + y = -1\n\nTo keep this simple I will multiply all the components of the 2x + 3y = -13 equation by negative 2, resulting in:\n\n-4x - 6y = 26\n\nThen add the new equation to the other equation 4x + y = -1\n\n-4x -6y = 26\n4x + y = -1\n----------------\n0x -5y = 25  which simplifies to y = -5\n\nInsert the value found for y back into one of the original eqations and solve for x\n\n2x + 3(-5) = -13\n\n2x + -15 = -13\n\n2x = 2\n\nx = 1\n\nYour end result is x =1 and y = -5
1063248
To solve correctly, distribute two to x and -2, add four to both sides, and divide both sides by x:\n\n2(x - 2) = x + 3\n2x - 4 = x + 3\n2x = x + 7\nx = 7\n\nThe error that was made was trying to simply remove the parentheses instead of actually distributing 2 to both of its contents.\n\n-----\n\nIf this is not what you meant and I have read it backwards, this is the other interpretation:\n\n-----\n\nTo solve correctly, add two to both sides, then divide both sides by x:\n\n2x - 2 = x + 3\n2x = x + 5\nx = 5\n\nThe error that was made was trying to change 2x [2 times x] into 2(x - 2) [2 times the difference of x and 2]. This is not allowed.