The discriminant is b<span>²-4ac
We can rewrite x</span>² = 4 to x<span>² + 0x - 4 = 0
So a = 1, b = 0, c = -4
</span>Δ = 0 - 4 * 1 * -4
Δ = 16
The answer is B
Answer:
D
Step-by-step explanation:
D's equation shows y equals 7.8 times x. 7.8 is the unit rate.
Answer:
x = 4y - 20
Step-by-step explanation:
x = Sadie's weight
y = Ben's weight
x = 4(y - 5)
x = 4y - 20
Answer:
The man is 27 years old.
Step-by-step explanation:
You can create a system of equations.
Let x = the age of the man
Let y = the age of his son
You can create the following equations based on what was given in the problem:
1. x = y + 18
2. (x - 3) = 4(y - 3)
You can simplify the second equation:
x - 3 = 4y - 12
x = 4y - 9
Then, solve the system of equations:
x = y + 18
-
x = 4y - 9
____________
0 = -3x + 27
The son's age is 9, therefore the father is 27 years old.
