Exponents - GRE Quantitative Reasoning

Card 1 of 584

0
Didn't Know
Knew It
0
1 of 2019 left
Question

What is the value of t if: 3x2 + tx - 21 = (3x - 3)(x + 7)?

Tap to reveal answer

Answer

Use the foil method: (3x - 3) (x + 7) = 3x2 +21x - 3x - 21 = 3x2 +18x -21 so t = 18.

← Didn't Know|Knew It →