Question

Solve for a.

25=a2+b2



A: a=5−b or a=5+b

B: a=25−b^2
C: a=±25−b^2−−−−−−√
d: a=±25+b2−−−−−−√

Answer 1

The correct answer is: [C]: " a = ±
`√(25 - b^2)` " .
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Explanation:
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We are given:
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→ " 25 = a² + b² " ; Solve for "a" ;
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→ To solve for "a" ; we want to isolate "a" on one side of the equation.
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We can rewrite: " 25 = a² + b² " ;

as: " a² + b² = 25 " .

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Then, we can subtract " b² " from each side of the equation; as follows:
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→ " a² + b² − b² = 25 − b² " ;

to get:
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→ " a² = 25 − b² " ;
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→ Now, take the square root of EACH SIDE of the equation ;
to isolate "a" on one side of the equation; & to solve for the value(s) of "a" ;
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→ √(a²) =
`√(25 - b^2)` ;

to get:
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→ a = |
`√(25 - b^2)` | ;

→ a = ±
`√(25 - b^2)` ;

→ which is: Answer choice: [C]: " a = ±
`√(25 - b^2)` " .
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