Sagot :
Answer:
The Co-ordinate of C is (4/3, -1/2)
Step-by-step explanation:
We have two equation one is of straight line equation which is:
y=2x-3 (i)
Other equation is of quadratic function which is:
y=-3x^2+5 (ii)
Put the value of y from equation (i) in equation (ii)
So, we have:
2x-3=-3x^2+5
3x^2+2x-8=0
By factorization:
3x^2+6x-4x-8=0
3x(x+2)-4x(x+2)=0
(x+2)(3x-4)=0
x+2=0 ; 3x-4=0
x=-2 ; x=4/3
Put first x=-2 in equation (i)
y=2(-2)-3
y=-4-3
y=-7
Now Put x=4/3 in equation (i)
y=2(4/3)-3
y=8/3-3
y=-1/2
So, we have two Order pair One is (-2 , -7) and Second one is (4/3 , -1/2)
Hence the Co-ordinate of C is:
C=(4/3 , -1/2)
Answer:
Point C: (3, 3)
Point D: (3, -22)
Step-by-step explanation:
If the distance between points C and D is 25 units, the y-value of point D will be 25 less than the y-value of point C. The x-values of the two points are the same.
Therefore:
[tex]\textsf{Equation 1}: \quad y=2x-3[/tex]
[tex]\textsf{Equation 2}: \quad y-25=-3x^2+5[/tex]
As the x-values are the same, substitute the first equation into the second equation and solve for x to find the x-value of points C and D:
[tex]\implies 2x-3-25=-3x^2+5[/tex]
[tex]\implies 3x^2+2x-33=0[/tex]
[tex]\implies 3x^2-9x+11x-33=0[/tex]
[tex]\implies 3x(x-3)+11(x-3)=0[/tex]
[tex]\implies (x-3)(3x+11)=0[/tex]
[tex]\implies x=3, -\dfrac{11}{3}[/tex]
From inspection of the given graph, the x-value of points C and D is positive, therefore x = 3.
To find the y-value of points C and D, substitute the found value of x into the two original equations of the lines:
[tex]\begin{aligned} \textsf{Point C}: \quad 2x-3 & =y\\2(3)-3 & =3\\ \implies & (3, 3)\end{aligned}[/tex]
[tex]\begin{aligned} \textsf{Point D}: \quad -3x^2+5 & = y \\ -3(3)^2+5 & =-22\\ \implies & (3, -22)\end{aligned}[/tex]
Therefore, point C is (3, 3) and point D is (3, -22).