If you would like to know the value of b^2 - 4 * a * c, you can calculate this using the following steps:
x * (x + 8) = 9
x^2 + 8x - 9 = 0
ax^2 + bx + c = 0
a = 1
b = 8
c = - 9
D = <span>b^2 - 4 * a * c = 8^2 - 4 * 1 * (-9) = 64 + 4 * 9 = 64 + 36 = 100
The correct result would be 100.</span>
Answer:
Mary = 24
Chau = 15
David = 48
Step-by-step explanation:
The formula is
Mary + Chau + David = 87
And we know that
Chau = Mary - 9
David = Mary * 2
So when we fill this in
Mary + Mary - 9 + Mary * 2 = 87
4Mary - 9 = 87
4Mary = 96
Mary = 24
Chau = Mary - 9 = 15
David = Mary * 2 = 48
The circumference of a circle is determined by the formula 2πr.
I'd say divide the circumference by two and youll be left with 60.5=πr .
then divide 60.5 by 3.14 to get r
which is approximately 19.26
now use the circle formula for area
A=πr²
A in terms of pi is
A = π*(19.26)²
