If x+✓y=7 and ✓x+y=11 then find x and y
BUT WITHOUT HIT AND TRIAL METHOD
I WILL MARK HIM BRAINLIEST
Answers
Answer:
x = 4, y = 9
Step-by-step explanation:
We have,
(i) x + √y = 7
(ii) √x + y = 11
Equation (i) can be written as,
⇒ √y = 7 - x
On squaring both sides, we get
⇒ y = (7 - x)² ------- (iii)
Now,
Let √x = t, then x = t². --------- (*)
Equation (4) can be written as,
⇒ t + (7 - x)² = 11
⇒ t + (7 - t²)² = 11
⇒ t + 49 + t⁴ - 14t² = 11
⇒ t⁴ - 14t² + t + 38 = 0
⇒ t⁴ - 2t³ + 2t³ - 4t² - 10t² + 20t - 19t + 38 = 0
⇒ t³(t - 2) + 2t²(t - 2) - 10t(t - 2) - 19(t - 2) = 0
⇒ (t - 2)(t³ + 2t² - 10t - 19) = 0
⇒ t - 2 = 0, t³ + 2t² - 10t - 19 = 0{Neglect}
⇒ t = 2.
From (*), we get
⇒ x = t²
⇒ x = 4.
Substitute x = 4 in (ii), we get
⇒ √x + y = 11
⇒ √4 + y = 11
⇒ 2 + y = 11
⇒ y = 9
Therefore, the values are x = 4 and y = 9.
Hope it helps!
√x+y=7x+√y=11√x=7-y√y=11-xthe square root of a number is always the positive square roottherefore y can't be greater than 7 and x can't be greater than 11look at the perfect squares 1, 4, 9, 16assuming x and y are perfect squares and a little trial and error...x=9 and y=4