You found CD from the Pythagorean theorem to be ...
... CD = √(5² -2²) = √21
Since triangle ADC ~ triangle ACB, the ratios of corresponding sides are the same:
... AC/AD = AB/AC
... AB = AC²/AD
... AB = 5²/2 = 12.5 . . . . . . . the base of the overall triangle
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Then the area (A) is ...
... A = (1/2)bh
... A = (1/2)(12.5)(√21) ≈ 28.64 square units
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As you see here, the altitude of a right triangle divides it into three similar triangles. From smallest to largest, they are ...
... ADC ~ CDB ~ ACB
You can figure this using AAA similarity, since the smallest and largest triangles listed above share an acute angle vertex (∠A). That, together with the right angle, means all angles are congruent. After that, then you know ∠ACD ≅ ∠CBD, so you can show the middle sized triangle is similar to the other two.
That is basically splitting the sentence so that it’s easier for you to solve it. It’s basically the same thing
C.supplementary is the right one
For any right triangle, we can use the Pythagorean Theorem. The Pythagorean Theorem states that for any right triangle, the legs when squared and added together will be equal to the hypotenuse squared.
In mathematical notation:

Where the variables a and b are the legs and the variable c is the hypotenuse.
Because we know the two side lengths of the triangle, we can solve for the unknown side.
We know the length of one of the legs and the hypotenuse.
Plug in the values.


So, the square root of 476 is the unknown length.
Answer:
See below in bold.
Step-by-step explanation:
The cost of what he wants to buy = 4.25 + 0.89 + 10.99
= $16.13
a) He does have enough to buy everything.
b) He has 20 - 16.13 = $3.87 left over.