Answer:
Your friend scored 62
Step-by-step explanation:
Let your friend's score = x
140/100 * x = 86.8 Starting statement
1.4x = 86.8 % has been changed to a decimal
1.4x = 86.8/1.4 Divide by 1.4
x = 86.8/1.4
x = 62 Answer
Check the picture below
so.. .hmmm the vertex is at the origin... and we know the parabola passes through those two points... let's use either.. say hmmm 100,-50, to get the coefficient "a"
keep in mind that, the parabolic dome is vertical, thus we use the y = a(x-h)²+k version for parabolas, which is a vertical parabola
as opposed to x = (y-k)²+h, anyway, let's find "a"

now.. .your choices, show.... a constant on the end.... a constant at the end, is just a vertical shift from the parent equation, the equation we've got above.. is just the parent equation, since we used the origin as the vertex, it has a vertical shift of 0, and thus no constant, but is basically, the same parabola, the one in the choices is just a shifted version, is all.
Answer:
34
Step-by-step explanation:
Marcy got 15% of the 40 wrong
.15 *40
6
If she got 6 wrong, then she got the rest right
40-6 = 34
She got 34 right
Answer:
that's the simplified way 24×15×38
Answer:
d.
Step-by-step explanation:
if x varies directly as y,
x = ky
8 = 12k
12k = 8
k = 8/ 12
k = 2/3,
x = 2/3 y
now substitute the value of any of the numbers of each pair, and check if it works:
for e.g, find x when y = 15
x = 2/3y
x = 2/3 × 15
x = 10
since you obtain x = 10 when y = 15, the pair is a possible corresponding value of x and y. now do the same for the rest .
ii) x = 2/3y
x = 2/3 × 3, when y = 3
x = 2
hence, this is also a possible pair of x and y values.
iii) x = 2/3y
x = 2/3 × 9 when y = 9
x = 6
again, a possible pair of x and y values.
iv) x = 2/3y
x = 2/3 × 20 when y = 20
x = 40/3
here, when y = 20, x is not 15. it is 40/3.
thus, it can be determined that this is not a possible pair of x and y values.
please try to understand and have a great day!