-9 to 0 is 9 and 0 to 14 is 14.
Total distance = 9 +14 = 23
17) replace the given number for "x" and evaluate
a) x² + 2x + 1 ; when x = 3
3² + 2(3) + 1
= 9 + 6 + 1
= 16
b) x² + 2x + 1 ; when x = -4
(-4)² + 2(-4) + 1
= 16 - 8 + 1
= 9
c) x² + 2x + 1 ; when x = 3
(-22.872)² + 2(-22.872) + 1
= 523.128384 - 45.744 + 1
= 478.384384
18) The dependent variable is affected by the other variable and is the "output" The independent variable is the input.
a) y = 3x - 5; "x" is the independent variable
b) the time of day is the independent variable (you would input the time of day to calculate the temperature).
19) Let the x-axis represent the length of the lumber cut off and the y-axis represent the length of the lumber remaining.
The answer is C.
The definition of a "quadratic equation" is any equation that has a variable with an unknown value to a power no less than or more than 2. A is not the answer because nothing is to the 2nd power. B, although is to the second power, is simplified into just 4, so it has neither an unknown variable nor power of 2. D is also incorrect because when the 3 is distributed, the equation is just simply 12-3x, which has no power of 2. So C is correct because when the 7x is distributed, you get the equation 7x^2 +21x, which has both a variable with an unknown value and a power of two.
