Question

The base of a triangle is seven less than twice its height. If the area of the triangle is 100cm^2 find the length of the base

Answer 1

Okay i got lets work itAnswer:

h≈4.874 cm,b≈21.748 cm

Explanation:

Atriangle=12bh

"The base of a triangle is twelve more than twice its height."

From this we can say that:

b=2h+12

So, if A=12bh, we can replace b with 2h+12.

A=12(2h+12)h

53=12(2h+12)h

53=(h+6)h

53=h2+6h

h2+6h−53=0

Use the quadratic formula.

h=−6±√62−4(−53)(1)2

h≈4.874

(Ignore the negative answer—height can't be negative.)

b≈2(4.874)+12

b≈21.748

Answer 2

2x-7 * x
----------- =. 100^2= 10000 
     2


2x^2-7/2= x^2-7/2

x^2-7/2=10000

x^2 = 20007/7