5x^2 - (2x - 3)^2 =
5x^2 - ((2x - 3)(2x - 3)) =
5x^2 - (4x^2 - 6x - 6x + 9) =
5x^2 - (4x^2 - 12x + 9) =
5x^2 - 4x^2 + 12x - 9 =
x^2 + 12x - 9 <===
The best answer is D.
According to the pythagorean theorem, a^2+b^2=c^2 in a right triangle where a and b are the legs and c is the hypotenuse.
The diagram given gives the length of both legs, so plug it into the equation to get c^2= 24^2+45^2
<h3>
Answer: B. 781.6 feet approximately</h3>
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Work Shown:
The horizontal portion is 400+166 = 566 feet. Label this as 'a', so a = 566. The vertical side is unknown, so b = x. The hypotenuse is c = 965
Use the pythagorean theorem
a^2+b^2 = c^2
566^2+x^2 = 965^2
x^2 = 965^2 - 566^2
x = sqrt( 965^2 - 566^2 )
x = 781.58108984289 which is approximate
x = 781.6 feet when rounding to one decimal place
<h3>Given</h3>
trapezoid PSTK with ∠P=90°, KS = 13, KP = 12, ST = 8
<h3>Find</h3>
the area of PSTK
<h3>Solution</h3>
It helps to draw a diagram.
∆ KPS is a right triangle with hypotenuse 13 and leg 12. Then the other leg (PS) is given by the Pythagorean theorem as
... KS² = PS² + KP²
... 13² = PS² + 12²
... PS = √(169 -144) = 5
This is the height of the trapezoid, which has bases 12 and 8. Then the area of the trapezoid is
... A = (1/2)(b1 +b2)h
... A = (1/2)(12 +8)·5
... A = 50
The area of trapezoid PSTK is 50 square units.
