Isabella was asked to determine whether f(x)=3x4+6x−2 is even, odd, or neither. Here is her work. Step 1: Find the expression for f(−x). f(−x)=3(−x)4+6x−2=3x4+6x−2 Step 2: Check if f(−x) is equal to f(x) or −f(x). f(−x)=f(x), and f(−x)≠−f(x). Step 3: Conclude that f(−x) is equivalent to f(x), so f must be even. Is Isabella's work correct? If not, what is the first step where Isabella made a mistake? Isabella's work is correct.

Isabella's work is not correct. She made her first mistake in step 3.

Isabella's work is not correct. She made her first mistake in step 2.

Isabella's work is not correct. She made her first mistake in step 1.

step-by-step explanation:

goog be able to you with that maybe

(b) 240

step-by-step explanation:

first, we use the pythagorean formula using the given side lengths to find x. then we use x to find the side lengths. then we add the side lengths to find the perimeter.

pythagorean theorem formula:

a^2 + b^2 = c^2

(x - 20)^2 + (x - 40)^2 = x^2

x^2 - 40x + 400 + x^2 - 80x + 1600 = x^2

x^2 -120x + 2000 = 0

(x - 100)(x - 20) = 0

x - 100 = 0 or x - 20 = 0

x = 100 or x = 20

we see that the solution x = 20 must be discarded because it will give a negative side length and a side length of 0. the only valid solution is x = 100.

perimeter = sum of the lengths of the sides

perimeter = x + x - 20 + x - 40

perimeter = 3x - 60

replace x with 100.

perimeter = 3(100) - 60

perimeter = 300 - 60

perimeter = 240