101k views
19 votes
4x + 7y =50 x = -y + 8
I NEED HELP!!

2 Answers

10 votes

Answer: (x, y) = (2, 6)

This means x = 2 and y = 6 pair up together

=========================================================

Step-by-step explanation:

Since x = -y+8, we can replace every copy of x with (-y+8) and we get

4x+7y = 50

4(-y+8)+7y = 50

-4y+32+7y = 50

3y+32 = 50

3y = 50-32 .... subtracting 32 from both sides

3y = 18

y = 18/3 .... dividing both sides by 3

y = 6

Use this y value to find x

x = -y+8

x = -6+8

x = 2

So we have the solution (x, y) = (2, 6)

If you were to graph the original two equations on the same xy coordinate grid, you should find that they intersect at (2,6).

User Fefwfefefwfwe
by
5.9k points
2 votes

Answer:

(2, 6 )

Step-by-step explanation:

Given the 2 equations

4x + 7y = 50 → (1)

x = - y + 8 → (2)

Substitute x = - y + 8 into (1)

4(- y + 8) + 7y = 50 ← distribute and simplify left side )

- 4y + 32 + 7y = 50

3y + 32 = 50 ( subtract 32 from both sides )

3y = 18 ( divide both sides by 3 )

y = 6

Substitute y = 6 into (2) for corresponding value of x

x = - 6 + 8 = 2

solution is (2, 6 )

User Alioguzhan
by
5.9k points