Discover a world of knowledge at Westonci.ca, where experts and enthusiasts come together to answer your questions. Get expert answers to your questions quickly and accurately from our dedicated community of professionals. Experience the convenience of finding accurate answers to your questions from knowledgeable experts on our platform.

The area of a triangle is 384 sq ft. If it's base is 8 ft longer than its height. Find the length of the base and height.

Sagot :

luana
[tex]x-\ base\\ y- \ height\\\\ x-8=y\\ Area=\frac{1}{2}xy\\\\ 384=\frac{1}{2}*x(x-8)\\ 768=x^2-8x\\ x^2-8x-768=0\\(x-32)(x+24)=0\\\\ x=32\\\\y=32-8=24\\\\Length\ of\ base\ is\ 32\ and\ height\ 24.[/tex]
Recall that Area of Triangle =  (1/2) *base* height.

Let the height = x.
And statement said base = 8 ft longer than height = (x+8)

Therefore:    A = (1/2)x(x+8)
                   384 = x(x+8)/2                Cross Multiplying
                    768 = x^2 + 8x     Re arrange, this is a quadratic equation.
                    x^2 + 8x = 768
                    x^2 + 8x - 768 = 0.   For quadratic factoring we think  of two numbers that would multiply to give -768 and add up to give +8.

By search, the numbers are 32 and -24.     32*-24 = -768 and (32+ -24) = 32-24 =8.

Solving:
x^2 + 8x - 768 = 0                                  Replace 8x with (32x -24x)
x^2 + 32x -24x -768 =0
x(x+32) -24(x+32)  = 0
(x+32)(x -24) = 0        Therefore (x+32) = 0  x = 0-32 =-32.
                                                (x-24) = 0  x = 0+24 =24.
x = -32 or 24.  
But our length can not be negative. Therefore x = 24. We throw away the negative answer.

Recall height = x = 24 ft.
Base = (x +8) = (24+8) = 32 ft.

Base = 32 ft, Height = 8ft. That's our answer. Hurray!