Answer: the first one i think
Step-by-step explanation:
Answer:
Bob is 17 years old
Mary is 22 years old
Step-by-step explanation:
Mary's current age: m
Bob's current age: b
m + b = 39
m = b + 5
Substitute.
b + 5 + b = 39
2b + 5 = 39
2b = 34
b = 17
m = 22
➣ Assignment:
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➣ Answer:
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Explanation: ↓↓↓↓↓
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➤ [ Step One ] Follow PEMDAS Order Of Operations
➤ [ Step Two ] Rewrite Equation
➤ [ Step Three ] Calculate Within Parenthesis
➤ [ Step Four ] Rewrite Equation
➤ [ Step Five ] Multiply
➤ [ Step Six ] Rewrite Equation
➤ [ Step Seven ] Calculate Exponents
➤ [ Step Eight ] Rewrite Equation
➤ [ Step Nine ] Solve
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Since f(x) is (strictly) increasing, we know that it is one-to-one and has an inverse f^(-1)(x). Then we can apply the inverse function theorem. Suppose f(a) = b and a = f^(-1)(b). By definition of inverse function, we have
f^(-1)(f(x)) = x
Differentiating with the chain rule gives
(f^(-1))'(f(x)) f'(x) = 1
so that
(f^(-1))'(f(x)) = 1/f'(x)
Let x = a; then
(f^(-1))'(f(a)) = 1/f'(a)
(f^(-1))'(b) = 1/f'(a)
In particular, we take a = 2 and b = 7; then
(f^(-1))'(7) = 1/f'(2) = 1/5
Well 26-5=21
And then you divide by 3(because it was tripled so) 21/3=7