Find the solution to the system of equations, x + 3y = 7 and 2x + 4y = 8.

1. isolate x in the first equation: x = 7 − 3y
2. substitute the value for x into the second equation: 2(7 − 3y) + 4y = 8
3. solve for y:
14 − 6y + 4y = 8
14 − 2y = 8
−2y = −6
y = 3
4. substitute y into either original equation: x = 7 − 3(3)
5. write the solution as an ordered pair:

Hello there!

here we have two equations:

1) x + 3y = 7

2) 2x + 4y = 8

a) first we want to isolate x in the first equation:

x + 3y = 7

x = 7 -3y

done!

b) now we want to replace it in the second equation, and in this way get a equation that depends only on the variable y.

2x + 4y = 8

2(7 - 3y) + 4y = 8

c) now we sole this equation and obtain the value of y.

14 - 6y + 4y = 8

14 - 2y = 8

-2y = 8 - 14 = -6

y = 6/2 = 3

d) now we have the value of y, and we can substitute it on the equation that we got in the part a)

x = 7 - 3y

x = 7 - 3*3 = 7 - 9 = -2

e) now we knowt that x = -2 and y = 3, then the pair (x,y) can be written as:

(-2,3).

i just took the test, the correct answer is .. 31.5 in.