Can someone help me with this? I've asked my teachers and I'm still lost

When keisha installed a fence along the 200 foot perimeter of her rectangular back yard, she left an opening for a gate. in the diagram below, she used x to represent the length in feet of the gate? what is the value? a. 10 b. 20 c. 25 d. 30

If (17, 4) is an ordered pair of the inverse of f(x), which of the following is an ordered pair of the function f(x)? a. (17,4) b. (4.17) c. (4,0) d. 0,17)

Solve the equation for x.3(6x - 1) = 12 i've tried doing the math and i can't find out what i'm doing wrong