Answer:
29
Step-by-step explanation:
Well "value" of 3x^2 - 7x + 9 when x = 4 is just x plugged into the expression
3 * 4^2 - 7 * 4 + 9
3 * 16 - 28 + 9
= 29
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:
9/-24 or ~ -0.38
Step-by-step explanation:
x y
3 9
12 -15
from 9 to -15 it will be subtracting 24
From 3 to 12 it will be adding 9
y/x = 9/-24 or -0.375 ~ -0.38
Answer:
Step-by-step explanation:
Before giving the exterior angles, find the third angle. A triangle (all triangles) measure 180 degrees.
35 + 80 + x = 180
115 + x = 180
x = 180 - 115
x = 65
Exterior angles are supplements of the interior angles.
So the exterior angle to 65 degrees is 180 - 65 = 115
And the exterior angle to 35 degrees is 180-35 = 145
The exterior angle to 80 degrees is 180 - 100 = 80