2/X^2=4/X+1 times by both denominators
2(x+1)=4(x^2)
2x+2=4x^2
4x^2-2x-2=0
(2x+1)(2x-2)=0
x=2x+1 or 2x-2
x=-1/2 or 1
Answer:
the angles in squares and rectangles it's always 90° so two squares or two rectangles with same side lengths are congruent.
You could rewrite
as
and be tempted to cancel out the factors of
. But this cancellation is only valid when
.
When
, you end up with the indeterminate form
, which is why
is not a zero.
There are a number of ways this can be done. One that is fairly simple is as follows.
Triangle ABC has base AC = 9 and height B to AC of 3 (found by counting squares). Thus its area is ∆ABC = (1/2)·9·3 = 13.5 square units.
Triangle ACF has base AC = 9 and height F to AC of 3, so will have the same area as triangle ABC, 13.5 square units.
Trapezoid CDEF has base CD of 6, base EF of 4 and height EF to CD of 6 (found by counting squares). Thus its area is CDEF = (1/2)(6 + 4)(6) = 30.
The total area of the entire figure is then
... ∆ABC + ∆ACF + CDEF = 13.5 + 13.5 + 30 = 57 square units.
