Question Video: Evaluating Algebraic Expressions after Solving Exponential Equations | Nagwa Question Video: Evaluating Algebraic Expressions after Solving Exponential Equations | Nagwa

Question Video: Evaluating Algebraic Expressions after Solving Exponential Equations Mathematics • Second Year of Secondary School

Given that 7^(𝑥) = 49 and 4^(𝑦) = 64, find the value of 𝑥𝑦.

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Video Transcript

Given that seven to the 𝑥 power equals 49 and four to the 𝑦 power equals 64, find the value of 𝑥 times 𝑦.

Here, we start with what’s given. So if we could rewrite 49 as 7 to some power, we could figure out what 𝑥 would be. And same with 64, if we can make 64 be four to a certain power equal to 64, we know what 𝑦 would be. 49 is equal to seven squared. Therefore, 𝑥 would be equal to two. 64 is equal to four cubed. So 𝑦 is equal to three.

So 𝑥 times 𝑦 would be two times three which is equal to six.

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