7x+2y=57x+2y=5 how do you do it

The value of .

Solution:

Given equations:

7x + 2y = 57 ---------- (1)

x + 2y = 5 ---------- (2)

Subtract 2y from both sides of the equation (2).

x = 5 – 2y ---------- (3)

Substitute equation (3) in equation (1).

7(5 – 2y) + 2y = 57

35 – 14y + 2y = 57

35 – 12y = 57

Subtract 35 from both sides of the equation.

–12y = 22

Divide by 12 on both sides.

Substitute y value in equation (3).

Hence the value of .

step-by-step explanation:

question 1 is 8, question 2 is 9, question 3 is 24

step-by-step explanation:

now, the numbers they give you at the top are the key. from there, you just have to plug and chug! let's try 1, 2, and 3!

key: a=3, b=5, c=6

1. a+5

remember, a=3, so we plug that in to get 3+5=8

2. 15-c

c=6, so we plug that in to get 15-6=9

3. 4b

b=6, so we plug it in to get 4*6=24

time to try the rest on your own! if you put the answers below in a comment, i'll check them for you!