Linear regression line y=2.1x+130 predicts sales based on the money spent on advertising.
Linear regression represents the relationship between two variables. the value of y depends on the value of x.
x represents the dollars spent in advertising and y represents the company sales in dollars.
We need to find out sales y when $150 spends on advertising.
Plug in 150 for x and find out y
y = 2.1 x + 130
y = 2.1 (150) + 130
y= 445
The company expects $445 in sales
Answer:
Step-by-step explanation:
Rationalize the denominator of b. So, multiply the numerator and denominator by 

Now, find a +b

Combine like terms

Now find (a + b)²
(a +b)² = 

Hint: 
N+9
The other factor is n-6
Once multiple together, you will get the same equation again
Each variable used is the first letter of each of their names.
t+b+c=87
c=2t
b=t+7
Substitute for b and c
t+ (t+7)+2t= 87
4t+7=87
4t=80
t=20
Plug in the known t value.
c=2(20)
c=40
b=20+7
b=27
Final answer: Tammy=$20, Boris= $27, Carlos=$40
Are you sure there weren't any other numbers in the problem? You can't solve for the volume with out at least two numbers for length, width, or height. Or are you solving for a cube?