The answer would be 75 using the formula v=1/2(a)(c)(h)
The only way to solve if it is equal to something
assuming that the teacher wanted you to make it equal to zero do
0=-3x^2-21x-54
remember if we can do
xy=0 then assume x and y=0
so factor
0=-3x^2-21x-54
undistribute the -3
0=-3(x^2+7x+18)
remember 0 times anything=0 so
x^2+7x+18 must equal zero
use quadratice formula which is
if you have
ax^2+bx+c=0 then
x=

x^2+7x+18
a=1
b=7
c=18
x=

x=

x=

i=√-1
x=

the zerose would be
x=

or
D because one thousand nine hundred twenty divided by 8 equals two hundred and forty
Answer:
£9.80
Step-by-step explanation:
The calculation of the total value is given below:
Provided that that
The value of 20p coins is £2.80
So 1p = £2.80 ÷ 20
= £0.14
For 50p it would be
= £0.14 × 50
= £7
Now the total value is
= £2.80 + £7
= £9.80