Question

Solve: 5(x + 8) = 7(x − 2)

17

−17

27

−27

Solve: -1/2 x + 3 = −x + 7

1/2

8

−8

2

Answer 1

For the first one, 5(x) is 5x 5(8) is 40. That gives you 5x+40 on the left side. 7(x) is 7x and 7(-2) is -14.. That gives you 7x+ -14 on the right side. Add 7x to both sides. That gives you 12x+40 = -14. Now subtract 40 from both sides. 12x=-54, x is -4.5.

Answer 2

The second one: Subtract 3 from both sides. You're left with -1/2x=-x+4. Now add x to both sides. 1/2x=4. You can multiply both sides by 2/1 to make x a whole number, which makes the whole equation 1x=8, which means x is 8.

Answer 3

Ok well thats not one of my choices so is there a differnt way to solve it?

Answer 4

@KCB I apologize, I was trying to work it in my head. I will resolve it right now.

Answer 5

For the first one, you'll have to multiply out the parentheses. That's the only way to get x on one side by itself ;)

Answer 6

I apologize. Number 1 is positive 27.

5x+40=7x-14

Subtract 5x from both sides.

40=2x-14

Add 14 to both sides.

54=2x

x=27

Answer 7

Your fine im jus tryna learn how to solve it

Answer 8

@KCB (:

Answer 9

So here's how you go about it step by step:

5(x + 8) = 7(x − 2)
(=) 5x+40 = 7x-14

Then you can add or subtract to both sides of the equation to get X on one side by itself:

(=) 40 = 7x - 5x - 14
(=) 40+14 = 7x-5x
(=) 54 = 2x
(=) 27 = x

Answer 10

thank you . how would i solve the 1/2 one?

Answer 11

The second one is similar. Start by subtracting 3 from both sides of the equation, then add 1x, and you've got all the products of x on one side. Then you can divide/multiply to solve for x.

Answer 12

ok lemme try it

Answer 13

Sorry msloo - you got it right, of course, just trying to show how the equations change with each step :)

Answer 14

what do i add 1x to?

Answer 15

Both sides of the equation. Anything you do you have to do to both sides of the equation, for the equation to still be true.
So, after subtracting 3 from both sides:
-1/2x + 3 = −x + 7
(=) -1/2x = -x + 7 -3

If you add 1x to both sides, you get this:

(=) -1/2x + x = -x + x + 7 -3

-x + x equals zero for any x, so this is the same as

(=) -1/2x + x = 7 -3

So by adding 1x to both sides, you've effectively eliminated all instances of the variabe on the right side of the equation.

Answer 16

i got 2?

Answer 17

@opiesche haha, it's fine

Answer 18

No - but I see where it went wrong, just a small mistake at the last step. Continuing, if we have

-1/2x + x = 7 -3

that's equivalent to

(=) 1/2x = 4

So to get x on the left side, we have to multiply by 2 (not divide):

(=) x = 4*2

So the result is 8.

Answer 19

Make sense?

Answer 20

Yea now i do its jus the 1/2 part that confused me Thank you :)