Answer:
x^2-3y
5^2-3*8
25-24
1
Step-by-step explanation:
Answer:
1a) Length = 7x + 3 & Width = 4x - 2
1b) Area = 
1c) Area = 2774 sq. m
2. 
Step-by-step explanation:
1a)
The length given as words is "3 more than 7 times x"
The width given as words is "4 times x minus 2"
The expression for length would be 7x + 3
The expression for width would be 4x - 2
1b)
The area is length * width
Since we already know the algebraic expressions for length and width from part (a) above, we use the formula:
Area = (7x+3)(4x-2) = 28x^2 -14x + 12x - 6 = 28x^2 -2x -6
Area = 
1c)
Given x = 10, we put this into the area expression we found in (b) above.Let's see:

Area = 2774 sq. m
2.
We can group the first two terms and next two terms and write up:

That's the factored form.
Answer:
2520 gallons
Step-by-step explanation:
3000 gallons -780 gallons drained over 6 hours then add 300 gallons over three hours = 2520 gallons
This can be determined by finding the x-intercept. In doing so, we let y=0 to find the value of x.
y= 2x^2 -x -3
[0 = 2x^2 -x-3]÷2
0 = x^2 -1/2 x - 3/2
Complete the squares:
1/16 + 3/2 = x^2 - 1/2x + 1/16
25/16 = (x -1/4)^2
sqrt (25/16) = x - 1/4
+/- 5/4 = x - 1/4
Thus,
x = 1/4 + 5/4 = 3/2
x = 1/4 - 5/4 = -1
Thus, the graph crosses at x = 3/2 and x = -1.
Answer:
Randy has eight $5 bills and nine $1 bills
Step-by-step explanation:
Randy needs $50.00
And we know that he his only $1.00 short, so he has $49.00
let's define:
x = number of $1 bills that he has
y = number of $5 bills that he has.
then:
x*$1 + y*$5 = $49
We know that he has one more $1 bills than $5 bills.
we can write this as
x = y + 1
So we have a system of two equations and two variables:
x*$1 + y*$5 = $49
x = y + 1
First we can see that the variable "x" is isolated in the second equation, now we can replace that in the other equation:
x*$1 + y*$5 = $49
(y + 1)*$1 + y*$5 = $49
now we can solve this for y.
y*$1 + $1 + y*$5 = $49
y*($1 + $5) = $49 - $1 = $48
y*$6 = $48
y = $48/$6 = 8
He has 8 $5 bills
and we know that:
x = y + 1
x = 8 + 1 = 9
he has 9 $1 bills.