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Please Help Me I Don't Understand!

Please Help Me I Don't Understand!-example-1
User Chad Decker
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1 Answer

19 votes
19 votes

Answer:

101.4 units²

Explanation:

If RT = 12 and TU = 5 then

RU = RT + TU

= 12 + 5

= 17 units

If RS is 7 more than RU then

RS = RU + 7

= 17 + 2

= 24 units

The ΔRSU is a right triangle with the right angle at ∠RUS.

Therefore, use Pythagoras' Theorem to find SU:

⇒ RU² + SU² = RS²

⇒ 17² + SU² = 24²

⇒ SU² = 24² - 17²

⇒ SU² = 287

SU = √287 units

Area of ΔRST = 1/2 × base × height

= 1/2 × 12 × √287

= 101.6464461... units²

(Please note: The answer quoted above is accurate. The answer given in the answer options uses the rounded value of SU to 1 decimal place).

User HomerThinking
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2.5k points