8 a) y=x² stretched vertically by 8
That means (0,0) stays (0,0), and (1,1) becomes (1,8) and (-1,1) becomes (-1,8)
Answer: y = 8x²
8 b) y=x² compressed vertically by 1/5
Answer: y = (1/5) x²
9.
y = ax² + k through (-1,3) and (3,-13)
That means
3 = a (-1)² + k
-13 = a (3²) + k
Subtracting,
16 = a - 9a = -8a
a = -2
3 = -2 + k
k = 5
y = -2x² + 5
Check:
-2(-1)^2 + 5 = 3, good
-2(3)^2+5 = -18 + 5 = -13, good
Answer: a = -2, k = 5
Answer:
BE = 39/5 or 7.8
Step-by-step explanation:
As <ABC = <DBE trigonometric function is angle BAC and angle BED
so sin (<ABC) = sin(<DBE) and AC and BC , BD and BE
so AC/AB = DE/BE = 13/BE = 5/3
So now we cross multiply
BE = 13 × 3 over 5
13 × 3 = 39
and over 5 means
39/5 = 7.8
Answer:
Find the distance between (-1, 1) and (3, 4).
This problem is solved simply by plugging our x- and y-values into the distance formula:
D=(3−(−1))2+(4−1)2−−−−−−−−−−−−−−−−−−√=
=16+9−−−−−√=25−−√=5
Sometimes you need to find the point that is exactly between two other points. This middle point is called the "midpoint". By definition, a midpoint of a line segment is the point on that line segment that divides the segment in two congruent segments.
If the end points of a line segment is (x1, y1) and (x2, y2) then the midpoint of the line segment has the coordinates:
(x1+x22,y1+y22)
