Y = 3x
so
if x = 5 then y = 15
if x = 10 then y = 30
so a = 10 and b = 15
answer is B. second choice
a = 10 and b = 15
Finding perimeter is simple. All you do is add up all of the side lengths, and bada bing bada boom, you got the perimeter.
TO find perimeter you add all sides. But to find the totaly of each side, you will divide. So a triangle has 3 sides, so you divide 45 by 3 to get the sides length of:
15 cm each
~hope this helped :)