How do you use the Pythagorean Theorem to find the missing side of the right triangle with the given measures: b = 5, c = 8?

3 Answers
May 14, 2018

Side A is sqrt(39) or 6.244997998.

Explanation:

Right, let write down the Pythagorean Theorem equation or standard form of it. before we plug in the numbers.

a^2 + b^2 = c^2

Right, so that is the equation of Pythagorean Theorem. So let plug in the numbers of b and c.

a^2 + 5^2 = 8^2

So we have our values of b and c. Now, how do we find the missing number?

Well, let simplify thing further by squaring the numbers we have already.

a^2 + 25 = 64

We will now subtract 25 from both side which gives us:

a^2 = 39

Now we can square root the answer.

sqrt(a^2) = sqrt(39)

Now, we are left with this:
a = sqrt(39)

Now, I am unsure if you want decimals or not. But if you were to square 39 into your calculator by pressing a few keys, it would give you this unless you switched mode.

On my calculator model of TI-36XPro, I pressed "mode" and went to the bottom and switched from Hathprint to Classic which gives me decimals of square roots.

So the final answer is sqrt(39) or the decimal value of sqrt(39) is 6.244997998.

May 14, 2018

a = sqrt39

Explanation:

The Pythagorean Theorem is a^2 + b^2 = c^2

You can then substitute the numbers b and c to get:
a^2+5^2=8^2
a^2+25=64

You can then make a^2 on its own by -25
a^2=39

Then square root both sides to get:
a = sqrt39

May 14, 2018

If you are finding the hypotenuse

5^2+8^2=a^2

25+64=a^2

a=sqrt89

a=9.433981132

If c is the hypotenuse then

8^2-5^2=a^2

64-25=a^2

a=sqrt39

a=6.244997998