Question

If p = 4, q=3, and r=-2, then find the value of the algebraic expression.
(1) p²+q²-r²
(2) pq+qr-pr​

Answer 1

Answer:

1) 4^2 + 3^2 - -2^2 = 16 + 9 - 4 = 25 - 4 = 21

2) 4x3 + 3x(-2) - 4x (-2) = 12 + (-6) - (-8) = 12 - 6 + 8 = 20 - 6 = 14

Answer 2

Step-by-step explanation:

Given:

p = 4

q = 3

r = -2

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To find:

p² + q²- r²

pq + qr - pr

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Solution:

(1) p² + q² - r²

=> (4)² + (3)² - (-2)²

=> 16 + 9 - 4

=> 25 - 4

=> 21

Therefore, p² + q² - r² = 21 when, p = 4, q = 3 and r = -2

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(2) pq + qr - pr

=> (4)(3) +(3)(-2)

=> 12 - 6 + 8

=> 20 - 6

=> 14

Therefore, pq + qr - pr = 14 when, p = 4, q = 3 and r = -2

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