Question

please help, I really don't understand how I work out the answer to this question and my teacher didn't teach it to us very well :/ ​

Answer 1

7x+5x+18=90

12x=90-18

12x=72

x=6

Explanation:

pythagoras law

Answer 2

Smallest angle =

`7x`

`7 * 6 \\ = 42 \: \: degrees`

Explanation:

`7x + 5x + 18 = 90 \\ 12x = 90 - 18 \\ 12x = 72 \\ (12x)/(12) = (72)/(12) \\ x = 6 \\ \\ 7x \\ 7 * 6 \\ = 42 \: \: degrees \\ \\ 5x + 18 \\ 5 * 6 + 18 \\ 30 + 18 \\ 48 \: \: degrees \\`