Answer:
Explanation:
First, you gotta work out the hypotenuse of ABC, which is AC.
To do that, you need to figure out the scale factor between the two right-angled triangles. You can do that for this question because this is a similar shapes question.
12.5/5 = 2.5
The scale factor length between the two triangles is 2.5.
You can use 2.5 now to work out AC, so AC would be 13 x 2.5, which gives 32.5.
Now that you've got the hypotenuse and BC of ABC, you can use Pythagoras's theorem to work out the length of AB
Pythagoras's theorem =
![a^2 + b^2 = c^2](https://img.qammunity.org/2022/formulas/mathematics/high-school/j4z41hjxubsqkqwany0n0kaakzwutve7q3.png)
a = BC = 12.5
b = AB = we need to work this out
c = AC (the hypotenuse we just worked out) = 32.5
Let's both simplify and rearrange this at the same time so that we have our b on one side.
= 1056.25 - 156.25
b =
![√((1056.25 - 156.25))](https://img.qammunity.org/2022/formulas/mathematics/high-school/j496cu1i1d62tkt1uavrxmxmt7yc5lp7sx.png)
b =
![√(900)](https://img.qammunity.org/2022/formulas/mathematics/high-school/2slcn6934cd17ertfawz688r7263qh033b.png)
b = AB = 30 We've found b or AB, now we can work out the perimeter of ABC.
Perimeter of ABC = AB + BC + AC
= 30 + 12.5 + 32.5
= 75 Here's the perimeter for ABC.