The quadratic equation is given by:
y = 3x² + 10x - 8
The standard equation of a parabola is given by:
y = ax² + bx + c
Where a, b, c are constants
At point (4, 80):
80 = a(4)² + b(4) + c
16a + 4b + c = 80 (1)
At point (-3, -11):
-11 = a(-3)² + b(-3) + c
9a - 3b + c = -11 (2)
At point (-1, -15):
-15 = a(-1)² + b(-1) + c
a - b + c = -15 (3)
Solving equations 1, 2 and 3 simultaneously gives:
a = 3, b = 10, c = -8
Therefore the quadratic equation becomes:
y = 3x² + 10x - 8
Find out more on quadratic equation at: brainly.com/question/1214333
Let x = John's age now
half of what johns age was 4 years ago: (1/2)(x-4)
is equal to one third of what it will be in 5 years time: (1/3)(x+5)
(1/2)(x-4) = (1/3)(x+5)
3(x-4) = 2(x+5)
3x - 12 = 2x + 10
Answer:
Four boys and one girl.
Step-by-step explanation:
Total students wearing glasses = 5
Separate the students by x and x + 3. It is x + 3 for the boys because there are three more boys wearing glasses.
Girls = x
Boys = x + 3
Total = 5
<u>Calculate:</u>
x + x + 3 =5
2x + 3 =5
2x = 2
x = 1
Boys wearing glasses = (1) + 3 = 4
Girls wearing glasses = 1