Answer:
w=14
l=18
Step-by-step explanation:
To find the dimensions, create an equation for its area and solve for each using the area formula A = l*w. The dimensions given are A = 252, w for width and l= w+4 (4 more than the width).
The width is 14 so the length is l=w+4 or l= (14)+4 =18
Remember that the vertex form of a parabola or quadratic equation is:
y=a(x-h)^2+k, where (h,k) is the "vertex" which is the maximum or minimum point of the parabola (and a is half the acceleration of the of the function, but that is maybe too much :P)
In this case we are given that the vertex is (1,1) so we have:
y=a(x-1)^2+1, and then we are told that there is a point (0,-3) so we can say:
-3=a(0-1)^2+1
-3=a+1
-4=a so our complete equation in vertex form is:
y=-4(x-1)^2+1
Now you wish to know where the x-intercepts are. x-intercepts are when the graph touches the x-axis, ie, when y=0 so
0=-4(x-1)^2+1 add 4(x-1)^2 to both sides
4(x-1)^2=1 divide both sides by 4
(x-1)^2=1/4 take the square root of both sides
x-1=±√(1/4) which is equal to
x-1=±1/2 add 1 to both sides
x=1±1/2
So x=0.5 and 1.5, thus the x-intercept points are:
(0.5, 0) and (1.5, 0) or if you like fractions:
(1/2, 0) and (3/2, 0) :P
Answer:
9
Step-by-step explanation:
Compare your x2 + y2=81 to the following:
x^2 + y^2 = 81
The " ^ " symbol indicates exponentiation.
Now compare x^2 + y^2 = 81 to
x^2 + y^2 = r^2.
This is the standard equation of a circle of radius r centered at the origin, (0,0). You can see for yourself that 81 must equal r^2.
Taking the square root of 81, we get plus or minus 9.
But the radius must be positive, so we reject the -9 and take +9.
The radius is 9.
Answer:
16 - 5 
Step-by-step explanation:
