Check the picture below.
so the figure is really just 3 rectangles and two triangles.
simply get the area of all 5, sum them up, and that's the area of the figure.
recall that area of a triangle A = ½bh.
Answer:
45
Step-by-step explanation:
AEF is a similar triangle to ABC. that means it has the same angles, and the sides (and all other lines in the triangle) are scaled from the ABC length to the AEF length by the same factor f.
now, what is f ?
we know this from the relation of AC to FA.
FA = 12 mm
AC = 12 + 28 = 40 mm
so, going from AC to FA we multiply AC by f so that
AC × f = FA
40 × f = 12
f = 12/40 = 3/10
all other sides, heights, ... if ABC translate to their smaller counterparts in AEF by that multiplication with f (= 3/10).
the area of a triangle is
baseline × height / 2
aABC = 500
and because of the similarity we don't need to calculate the side and height in absolute numbers. we can use the relative sizes by referring to the original dimensions and the scaling factor f.
baseline small = baseline large × f
height small = height large × f
we know that
baseline large × height large / 2 = 500
baseline large × height large = 1000
aAEF = baseline small × height small / 2 =
= baseline large × f × height large × f / 2 =
= baseline large × height large × f² / 2 =
= 1000 × f² / 2 = 500 × f² = 500 ×(3/10)² =
= 500 × 9/100 = 5 × 9 = 45 mm²
Answer: The process of combining matrices, vectors, or other quantities under specific rules to obtain their product.
Answer:
-12
Step-by-step explanation:
Let the number be A
Given if you divide the sum of six and the number A by 3 , the result is 4 more than 1/4 of A
That’s
6+A/3 = 4+1/4 of A
6+A/3 = 4+1/4 x A
6+A/3 = 4+A/4
Cross multiply
4(6 + A) = 3(4 + A)
Distribute
4 x 6 + 4 x A = 3 x 4 + 3 x A
24 + 4A = 12 + 3A
Subtract 24 from both sides to eliminate 24 on the left side
24 - 24 + 4A = 12 - 24 + 3A
4A = -12 + 3A
Subtract 3A from both sides so the unknown can be on one side
4A - 3A = -12 + 3A - 3A
A = -12
Check
6+(-12)/3 = 4 +(-12)/4
6 -12/3 = 4 -12/4
-6/3 = -8/4
-2 = -2
