Answer:
k = -9
Step-by-step explanation:
f(x) = 2x²+kx-20
From remainder theorem,
x = 10 and f(10) = 90
f(10) = 90
Subsitute the value of x into the expression above.
f(10) = 2(10²)+10k-20 = 90
200+10k-20 = 90
Solve for k by collecting like terms
10 k = 90+20-200
10k = 110-200
10k = -90
k = -90/10
k = -9.
Hence the value of the constant is -9
Option B:

General formula for the height(feet) of a projectile over time:

where h represents height (feet)
t represents time
represents initial velocity
represents initial height(feet)
General formula for the height(metres) of a projectile over time:

where h represents height (feet)
t represents time
represents initial velocity
represents initial height(metres)
<u>Given data in the question:</u>
metre
m/s
To determine the equation to find time:
Substitute
and
in general formula for the height(metres) of a projectile over time:


Therefore option B is the correct answer.

Answer:B
Step-by-step explanation:
Answer:32%
Step-by-step explanation:
330-250=80
80/250=0.32 or 32%
Answer:
3^3×3
81
3^7/3^3
Explanation:
First you should solve the expression you've got there.
(3^6×3^-4)^2
3^6= 3×3×3×3×3×3 the answer is 729
3^-4 A negative exponent means repeated division by the base. So for example 2^-4=1/(2^4)
=1/(2×2×2×2)= 1/16
3^-4= 1/(3^4)
=1/(3×3×3×3)
= 1/81 If you look up the answer in your calculator the answer that will show up will be 0.01234567901
So!
(729×0.01234567901)^2= 9^2
9^2= 81
Now you can look at the following expressions and whichever gives the answer 81 will be correct.
hope it helps!