Maths-
SAT
Easy
Question
If x + y = 13 and x - y = 2, what is the value of x2 -y2 ?
- 4
- 26
- 121
- 165
The correct answer is: 26
x + y = 13 & x – y = 2
(x + y) (x – y ) = 13 × 2 = 26
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