I'm assuming that you meant:
y = 7x² + 3
Remember! Inputs are always x values (unless stated otherwise). Meaning the problem says:
x = 4
y = 7(4)² + 3
The square only applies to the 4. The 7 is not going to be squared! (To be exact it only applies to whatever the value of x is.
4² = 4·4 = 16
Remember:
Parenthesis
Exponents
Multiplication
Division
Addition
Subtraction
Follow PEMDAS from left to right (or in the case above from top to bottom).
7·16 + 3 = ?
16·7 = 10·7 + 6·7 = 70 + 42 = 112
(All I did to multiply was break it up into parts. If it confuses you don't worry about it, and just multiply it out like normal or use a calculator if you are allowed to)
112 + 3 = ?
Our output is:
115!
Answer:
18
Step-by-step explanation:
The average rate of change of f(x) in the closed interval [ a, b ] is
here [ a, b ] = [ 1, 5 ]
f(b) = f(5) = 3 × 5² = 75
f(a) = f(1) = 3 × 1² = 3, hence
average rate of change = 
= 
= 18
Here's link to the answer:
tinyurl.com/wpazsebu
