Answer:
f(x) = -(x-3)^2 + 4
Step-by-step explanation:
(h; k) are the coordinates of the vertex.
On the graph are (3, 4), therefore we have:
f(x) = a(x-3)^2 + 4
We have the x- intercept (1,0) -> x=1; y=0.
Substitute them into the equation:
0 = a(1 - 3)^2 + 4
0 = a(-2)^2 + 4
4a + 4 = 0 | -4
4a = -4 |-4
a = -1
So, we have the answer:
f(x) = -(x-3)^2 + 4
Answer:
x = - 2.5
Step-by-step explanation:
Given that the sketch represents
y = x² + bx + c
The graph crosses the y- axis at (0 , - 14), thus c = - 14
y = x² + bx - 14
Given the graph crosses the x- axis at (2, 0), then
0 = 2² + 2b - 14
0 = 4 + 2b - 14 = 2b - 10 ( add 10 to both sides )
10 = 2b ( divide both sides by 2 )
b = 5
y = x² + 5x - 14 ← represents the graph
let y = 0 , then
x² + 5x - 14 = 0 ← in standard form
(x + 7)(x - 2) = 0 ← in factored form
Equate each factor to zero and solve for x
x + 7 = 0 ⇒ x = - 7
x - 2 = 0 ⇒ x = 2
The x- intercepts are x = - 7 and x = 2
The vertex lies on the axis of symmetry which is midway between the x- intercepts, thus
the x- coordinate of the turning point is = = - 2.5
Answer:
What we know is that 30% of the group have brown hair and are girls. It means that in the other 70% we have the boys with brown hair, the other boys and the other girls.
In the case all the girls have brown hair, the 70% remaining would be boys. So 70% of then would have brown hair. (0.7*0.7=0.49 -> 49% of the children would be brown hair) so 49% (boys) and 30% (girls) are more than 50%..
Now, let's suppouse that 90% of the group are girls. It means 10% are boys and 70% of that 10% (=7%) are the boys in the group that have brown hair. Now 7% + 30% of the children have brown hair, wich isn't more than the half.
We have explained with two extreme cases that the information is not enough for making a precise answer
Answer:
Step-by-step explanation:
sorry i tried my best i think its like a 30
Y= 12 - x
27 + 3( 12 - x ) = 2x