Answer:
Associative property
Step-by-step explanation:
Associative property allows you to put parenthesis in a part of the equation. We can only apply associative property on a part with multiplication or addition. If you do it with at an equation with subtraction or division you can change the result and make calculation mistake.
In this question, all of the operation used is multiplication. The result won't change even if you put parenthesis, both will give result of 480
Answer:
x = 1
y = -1
z = 2
Step-by-step explanation:
You have the following system of equations:

First, you can subtract euqation (3) to equation (1):
x + 2y - z = -3
<u>-x +y -z = - 4 </u>
0 3y -2z = -7 (4)
Next, you can multiply equation (3) by 2 and subtract it to equation (2):
2[ x -y + z = 4]
<u> -2x +y -z = -5</u>
0 -y + z= 3 (5)
You multiply equation (5) by 2 and sum (5) with (4):
2[ -y + z = 3]
<u> 3y -2z= -7</u>
y + 0 = -1
Then y = -1
Next, you replace y=-1 in (5) to obtain z:
-(-1) + z = 3
z = 2
Finally, you can replace z and y in the equation (3) to obtain x:
x - (-1) + (2) = 4
x = 1
Answer:
See below
Step-by-step explanation:
linear equation: y=2x+10
x=cost per movie rented
10=$10 for the membership
24=2x+10 (24 being total you want to spend)
subtract 10 from each side
14=2x
divide by 2
7=x
He can rent no more than 7 movies if he want to spend $24 or less in the month
By exterior angle of triangle:
17x+4+8x+1=80
x=3