Question

4st^2-s^2 were s=5 and t=7

Answer 1

       ➣ Assignment: $\bold{Solve \ Equation: \ \left(4\left(5\cdot \:7^2\right)\right)-5^2}$

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       ➣ Answer: $\boxed{\bold{955}}$

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Explanation: ↓↓↓↓↓

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       ➤ [ Step One ] Follow PEMDAS Order Of Operations

$\bold{4\left(5\cdot \:7^2\right): \ 980}$

       ➤ [ Step Two ] Rewrite Equation

$\bold{4\left(5\cdot \:7^2\right)}$

       ➤ [ Step Three ] Calculate Within Parenthesis

$\bold{4\left(5\cdot \:7^2\right): \ 245}$

       ➤ [ Step Four ] Rewrite Equation

$\bold{4\cdot \:245}$

       ➤ [ Step Five ] Multiply

$\bold{4\cdot \:245: \ 980}$

       ➤ [ Step Six ] Rewrite Equation

$\bold{980-5^2}$

       ➤ [ Step Seven ] Calculate Exponents

$\bold{5^2: \ 25}$

       ➤  [ Step Eight ] Rewrite Equation

$\bold{980-25}$

       ➤  [ Step Nine ] Solve

$\bold{955}$

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$\bold{\rightarrow Mordancy \leftarrow}$