Question

HELP HELP HELP pls pls

Answer 1

6

Explanation:

`\triangle{PQR}` is a right triangle. Use the Pythagorean Theorem:

(leg)^2 + (leg)^2 = (hypotenuse)^2

The length of PR is r + 4; it's the hypotenuse.

`PQ^2+QR^2=PR^2`

`r^2+8^2=(r+4)^2 \\ r^2+64=r^2+8r+16 \\ 64=8r+16 \\ 48=8r \\ 6=r`

Remember, to expand
`(r+4)^2` you multiply
`(r+4)(r+4)`