Question

math solve questions
$9 - \sqrt{y - 4 = 5}$
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Answer 1

Answer:

y = 20

Step-by-step explanation:

$9 - \sqrt{y - 4} = 5$

i) move 9 to the right-hand side and change its sign

$- \sqrt{y - 4} = 5 - 9$

ii) calculate the difference

$- \sqrt{ y - 4} = - 4$

iii) change the signs on both sides of the equation

$\sqrt{y - 4} = 4$

iv) square both sides of the equation

$( \sqrt{y - 4} ) {}^{2} = 4 {}^{2}$

$y - 4 = 4 {}^{2}$

$y - 4 = 16$

v) move -4 to the right-hand side and change its sign

$y = 16 + 4$

vi) add the numbers

$y = 20$

Answer 2

Answer: y = 20

defined condition is y ≥ 4

$9 - \sqrt{y - 4}=5\\\\<=> \sqrt{y - 4}= 9-5\\\\\\<=>\sqrt{y-4}= 4\\\\\\=> y - 4 = 16\\\\\\<=> y = 16 + 4 = 20$

Step-by-step explanation: