Question

A: 502° CB: 6, 681° CC: 6, 135°CD: 47° C

Answer 1

The idea behind the problem is solving an equation involving square roots. The equation I'm talking about is

`358=20\cdot\sqrt[]{273+t}`

(I merely replaced v by 358; what we are supposed to do is to find t). Let's solve it:

1. 20 is multiplying at the right-hand side, let's send it to divide at the left:

`(358)/(20)=\sqrt[]{273+t}`

2. (this is the most important step) Take the power of 2 on both sides:

`((358)/(20))^2=273+t`

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Comment: Remember that

`(\sqrt[]{273+t})^2=273+t`

because square root and powering by two are inverse of each other.

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3. Put the left-hand side in a calculator to get:

`(128164)/(400)=273+t`

4. Let's subtract 273 to the left-hand side:

`320.41-273=t`
`47.41\degree C=t`