How do you solve 3( x + 4) = 8x + 7?

3 Answers
Apr 5, 2018

x = 1

Explanation:

3(x+4) = 8x + 7

First, we want to use the distributive property to solve. This means that we "distribute" or multiply the 3 with everything in its parenthesis:
3 * x = 3x

3 * 4 = 12

And when you combine them you get 3x + 12.

3x + 12 = 8x + 7

Now we subtract 3x from both sides of the equation:
12 = 5x + 7

Then we subtract 7 from both sides of the equation:
5 = 5x

Finally, we divide both sides by 5 to get the value of x:
x = 1

Apr 5, 2018

x=1

Explanation:

Solve:

3(x+4)=8x+7

Expand the left-hand side.

3x+12=8x+7

Subtract 12 from both sides. Cancel 12 on the left-hand side.

3x+color(red)cancel(color(black)(12))-color(red)cancel(color(black)(12))=8x+7-12

Simplify.

3x=8x-5

Subtract 8x from both sides. Cancel 8x on the right-hand side.

3x-8x=color(red)cancel(color(black)(8x))-color(red)cancel(color(black)(8x))+19

Simplify.

-5x=-5

Divide both sides by -5. Cancel -5 on the left-hand and right-hand sides.

(color(red)cancel(color(black)(-5))^1x)/(color(red)cancel(color(black)(-5))^1)=(color(red)cancel(color(black)(-5)))^1/(color(red)cancel(color(black)(-5)))^1

Simplify.

x=1

Apr 5, 2018

the answer is x=1

Explanation:

first you have to distribute 3 to it's equation and you get3x+12=8x+7 and now you solve. first get only one x so do 8x-3x and you'll end up with this12=5x+7 now subtract 7 from both sides. and now you have 5=5x and now divide 5 with the x from both sides. and you get your answer