Question

Find the value of 25x^2+ y^2 if 5x+y= 10 and xy=5

Answer 1

Answer:

Given,

5x+y=10

xy=5

$25x {}^{2} + y {}^{2} \\ = (5x) {}^{2} \ + (y) {}^{2} \\ = (5x + y) {}^{2} - 2 \times 5x \times y \\ = (5x + y) {}^{2} - 10xy \\ = (10) {}^{2} - 10 \times 5 \\ = 100 - 50 \\ = 50$

USED FORMULA :-

$a {}^{2} + b {}^{2} = (a + b) {}^{2} - 2ab$

Answer 2

Answer:

50

Step-by-step explanation:

$(a + b) {}^{2} = a {}^{2} + 2.a.b \:+ b {}^{2}$