Question

Write an equivalent expression for 8(3+5x)+ 7x+4 If x = 3, is the solution to both expressions the same?

Answer 1

Explanation:

Ok, this is a simple problem. All we have to do is plugin, go back to the original and simplify and lastly plugin

A)Lets start with part A: Plugging In

1. Lets replace all the x's with 3 so we get: 8*(3+5*3)+7*3+4
2. Now lets do everything in the parenthesis so we can remove the parenthesis and we get: 8*18+7*3+4
3. Now we can do all the multiplication and get: 144+21+4

Finally we finish part A with addition and get: 169

B)Lets put that aside and move onto part B

1. Simplifying 8(3+5x)+ 7x+4
2. First distribute 8 among 3+5x and we get: 24+40x+7x+4
3. Now we combine all like factors and get: 28+47x
4. Thats our expression that is equivalent to 8(3+5x)+ 7x+4

C)Now all we have to do is Part C which is plug 3 into 28+47x

1. First lets replace all the x's with 3 so we get: 28+47*3
2. Now lets do the multiplication and that is: 28+141
3. Finally lets finish with the addition: 169

And 169 is the same solution as the one it part A! So that means 28+47x is an equivalent expression to 8(3+5x)+ 7x+4