Question

The sum of two numbers is 10. The larger number is 4

times the smaller number. What are the two numbers?
Original system: x + y = 10,
y = 4x
Slope-intercept form:
y = -x + 10
y = 4x

Answer 1

2 and 8.

Explanation:

y = -x + 10

y = 4x

If we subtract we eliminate y:

0 = -x + 10 - 4x

0 = -5x + 10

5x = 10

x = 2.

and y = 4 * 2 = 8.

Answer 2

x=8 and y=2

Explanation:

x+y=10

x=4y

x+y=10

4y+y=10

5y=10(divide both sides by 5)

y=2

x=4y=4*2=8