Question

Find the length of the third side. If necessary, write in simplest radical form.

Answer 1

Answer:

$\boxed {\boxed {\sf 8}}$

Step-by-step explanation:

This triangle has a small square, which represents a right angle. Therefore, we can use the Pythagorean Theorem.

$a^2+b^2=c^2$

Where a and b are the legs of the triangle and c is the hypotenuse.

In this triangle, 7 and √15 are the legs, because these sides make up the right angle. The unknown side is the hypotenuse, because it is opposite the right angle. So, we know two values:

$a= 7 \\b= \sqrt{15}$

Substitute these values into the formula.

$(7)^2+(\sqrt{15})^2=c^2$

Solve the exponents.

• (7)²= 7*7=49

$49+ (\sqrt{15})^2=c^2$

• (√15)²=√15*√15=15

$49+15=c^2$

Add.

$64=c^2$

Since we are solving for c, we must isolate the variable. It is being squared and the inverse of a square is the square root. Take the square root of both sides.

$\sqrt{64}=\sqrt{c^2} \\\sqrt{64}= c\\8=c$

The third side length is 8.

Answer 2

Answer:

8

Step-by-step explanation: