SOLUTION:
Let whole number = x
x + 2x^2 = 21
2x^2 + x - 21 = 0
2x^2 + 7x - 6x - 21 = 0
x ( 2x + 7 ) - 3 ( 2x + 7 ) = 0
( 2x + 7 ) ( x - 3 ) = 0
2x + 7 = 0
2x = - 7
x = - 7 / 2
OR
x - 3 = 0
x = 3
ANSWER:
Therefore, as 3 is a whole number while - 7 / 2 isn't a whole number, the whole number must be 3.
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Answer:
9
Step-by-step explanation:
Area of kite is Area of triangles. Area is 6+3=9
Answer:
r equals StartFraction C Over 2 pi EndFraction
Step-by-step explanation:
we know that
The circumference of a circle is equal to

where
r is the radius of the circle
Solve for r
That means -----> isolate the variable r
Divide by 2π both sides

Simplify right side

Rewrite

so
r equals StartFraction C Over 2 pi EndFraction