To perform the function on x means to double x. To perform the function
twice would mean to double x and then to double the result—in effect
turning x into 4x. For some particular value of x, when you perform the
function twice, you end up with x + 1. Therefore, for this value of x, 4x and
x + 1 are the same:
36 . D
Because ℓ 1 and ℓ 2 are parallel, you will need to look for transversals.
Think of the two angles marked x° as one angle measuring 2x°. That
angle and the angle marked (4x – 30)° are exterior angles on the same
side of the transversal, so they add up to 180°:
37 . E
To get the total number of possibilities, multiply: 3 colors, 2 body types,
and 3 engine types means 3 × 2 × 3 = 18 different models.
38 . C
Solve the inequalities separately, then find their intersection: