Answer:
21
Step-by-step explanation:
<span>if exponent 2
4 • (2 + 5)^2 - 52
= </span>4 • (7)^2 - 52
= 4 • 49 - 52
= 196 - 52
= 144
if multiply by 2
4 • (2 + 5)2 - 52
= 4 • (7)2 - 52
= 4 • 14 - 52
= 56 - 52
= 4
Answer: -3°F
Step-by-step explanation:
From the question, we are informed that the temperature outside changed from 64°F to 43°F over a period of seven days. The total change will be:
= 43°F - 64°F
= -21°F
If the temperature changed by the same amount each day, the daily temperature change will now be:
= -21°F / 7
= -3°F
The temperature decreased by 3°F daily
Answer:
A linear relationship is a statistical term or phrase used to describe a straight line relationship between the two variables
Let x = amount of 65% antifreeze
Let y = amount of 90% antifreeze
EQUATION 1: x + y = 50 (total of 50 gallons mixed)
EQUATION 2: .65x + .90y = .70(x + y)
Simplify and solve the system of equations
Multiply second equation by 100 on both sides to remove the decimals
65x + 90y = 70(x + y)
Combine like terms
65x + 90y = 70x + 70y
65x -70x+ 90y-70y = 0
-5x + 20y = 0
Now we have the following system of equations:
x + y = 50
-5x + 20y = 0
Multiply the first equation by 5 to get opposite coefficients for x;
add the equations to eliminate x
5x + 5y = 250
-5x + 20y = 0
------------------------------
25y = 250
Solve for y
y = 10
Since the total mixed gallons is 50,
x = 50 - 10 = 40
So we need 40 gallons of the 65% antifreeze and 10 gallons of the 90% antifreeze
