Answer: 
Step-by-step explanation:
We know that the standard quadratic equation is ax^2+bx+c=0
Let's compare all the given equation to it and , find discriminant.
1. a=2, b= -7, c=-9
So it has 2 real number solutions.
2. a=1, b=-4, c=4

So it has only 1 real number solution.
3. a=4, b=-3, c=-1

So it has 2 real number solutions.
4. a=1, b=-2, c=-8
So it has 2 real number solutions.
5. a=3, b=5, c=3

Thus it does not has real solutions.
We can split this up into 3 rectangles. 2 vertical ones (8 x 3) and one horizontal one in the middle (5 x (8 - 5)
8 x 3 = 24
24 x 2 = 48
5 x (8-5) = 5 x 3 = 15
now add 48 + 15 = 63 cm^2
The answer is: 10.
Explanation: The numbers are in order by the median/lowest to highest so in that case X wouldn't be 7 because the X would have been next to the 7 not on the other side of the 10.
Answer:
60cm³
Step-by-step explanation: