Solve the system of equations using the substitution method.
-3x - y = 15
y = -8x

x = 3, y = -24

Step-by-step explanation:

-3x - y = 15

y = -8x

Substitute the value of y into the first equation.

-3x - (-8x) = 15

-3x + 8x = 15

5x = 15

x = 3

Put the value of x into the second equation.

y = -8 * 3

y = -24

unpaid balance is : $149.99-$50 = $99.99 new balance = 149.99+2.62-50 = $102.61 finance charge = 99.99- 0.21/12= $1.75 new balance = 99.99+1.75 = $101.74 average daily balance method average daily balance= 3399.70/30 = $113.32 finance charge = $ 0.21/12ă—113.32 = $1.98 new balance = $149.99-50+1.98 = $101.97

-2x + 7 = 7

subtract 7 from both sides.

-2x = 0

divide both sides by -2.

x = 0