Answer:
26.25 cm²
Step-by-step explanation:
The area of the shaded part is the area of the shaded triangle subtract the area of the white triangle.
Since the triangles are similar then the ratios of corresponding sides are equal.
let the height of the white triangle be h, then
=
( cross- multiply )
12h = 90 ( divide both sides by 12 )
h = 7.5
shaded area = × 12 × 10 -
× 9 × 7.5 = 60 - 33.75 = 26.25 cm²
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Work Shown:
The two points we have are and
Apply the distance formula
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A shortcut is possible by subtracting the y coordinates of the two points, and making the result positive through the use of absolute value.
So we either say
|y1-y2| = |1.2-2.5| = |-1.3| = 1.3
or,
|y2 - y1| = |2.5 - 1.2| = |1.3| = 1.3
We get the same result. This shortcut is valid because the x coordinates of both points are the same.