i am in accelerated algebra 3 and i cant figure this out. The case of a triangle measures 4cm less than the altitude. if the area is 30 square centimeters, find the dimensions of the triangle.
2007-09-01 17:47:12 · 3 answers · asked by Anonymous in Science & Mathematics ➔ Mathematics
x= altitude
x-4 = base
30 = area
we know that the formula for the area of a triangle is
area= (base)(height)(1/2)
so just substitute the values
30= (x-4)(x)(1/2)
60 = x-4(x)
60=x^2-4x
x^2-4x-60=0
factor
(x-10)(x+6)=0
x-10=0 ; x+6=0
x=10 ; x=-6
there is no negative measurement so the answer is
x=10
therefore...
altitude= x = 10
base= x-4 = 6
the altutude is 10cm while the base is 6 cm
2007-09-01 18:32:12 · answer #1 · answered by mockingbird 3 · 0⤊ 0⤋
Easy Easy Easy. Area= 1/2(b)(h)
30 = 1/2 bh
60=bh
b= h-4
60=(h-4)(h)
h^2 - 4h= 60
h^2 -4h - 60=0 Factor
(h-10)(h+6)
Height = 10 (cant be -6, height cant be negative)
Base + 10-4 = 6
Check 1/2 (10)(6) = 30
2007-09-01 17:58:54 · answer #2 · answered by pianostud06 2 · 0⤊ 0⤋
" Case " of a triangle???!!!!
Let BASE = b and altitude = h
30 = (1/2) (b) (h)
30 = (1/2) (h - 4) (h)
60 = h² - 4h
h² - 4h - 60 = 0
(h - 10) (h + 6) = 0
h = 10
Height = 10 cm
Base = 6 cm
2007-09-01 23:24:06 · answer #3 · answered by Como 7 · 0⤊ 0⤋