Answer:
y = -6
x = 1
Step-by-step explanation:
-x + 2y = -13
-x - 2y = 11
Sum the equations:
-x -x = -2x
+2y - 2y = 0
-13 + 11 = -2
then
-2x = -2
x = -2/-2
x = 1
from the first eq.
-x + 2y = -13
-1 + 2y = -13
2y = -13 + 1
2y = -12
y = -12/2
y = -6
check:
from the second eq.
-x -2y = 11
-1 -(2*-6) = 11
-1 -(-12) = 11
-1 + 12 = 11
$5 each car
3 hours = 12 cars
÷3 ÷3
1 hours = 4 cars
×8 ×8
8 hours = 32 cars
32 cars × $5 per car =
$160
They earned $160 in 8 hours, from washing 32 cars.
Answer:
a - b = 12
Step-by-step explanation:
Given
= 12 ← factor the numerator
a² - b² ← is a difference of squares and factors as
a² - b² = (a - b)(a + b)
Thus
= 12
Cancel the common factor (a + b) on numerator/ denominator, thus
a - b = 12
Answer:


Step-by-step explanation:
Marginal average Cost function:

Marginal average Revenue function:

Answer:
101in
Step-by-step explanation:
9*5=45
9*4=36
5*4=20
45+36+20=101