Dr Gulshan S. answered • 02/17/21
Experienced Physics Tutor with a PhD
The equation for a parabola has the form y=ax2 +bx+c where a ,b and, c are constants and a≠0 Find an equation for the parabola that passes through the points (3,9), (1,5) and (4,17)
As the Parabola passes through ( 3,9)
X = 3 , Y = 9
plug in the equation
9 = 9a +3b + c ....... Eq 1
Next point (1,5)
.
X= 1, Y = 5
5 = a + b + c ........ Eq 2
Third point
(4,17 )
X = 4, Y = 17
17 = 16a + 4b +c ..... Eq 3
Sove these three Equation for a, b and c
By substitution 8a + 2b = 4 and 15a +3b = 12
a= 2 , b = 3
c = -18
Equation of parabola is
y= 2X2 +3X-18
Please check the answer and inform me , if you have a questioin
KRIKO S.
The correct answer is y=2x^2 +-6x +902/17/21
Dr Gulshan S.
You recheck the three equations and solve for a,b and c May be I have done in a hurry 👍02/17/21
Dr Gulshan S.
If you want me do it again just let me know02/17/21
Dr Gulshan S.
From Eq 1, 2 and 3 If we Subtract to eliminate c we get 8a+2b = 4 and 15a +3b = 12 Solving therse two equations we get a= 2 , b= -6 and c= 9 Hence equation of parabola is y = 2X^2 -6 X +9 Excuse me for solving in a hurry02/18/21
KRIKO S.
Hello sir, thank you for your help, After checking with the teacher and the Homework Software, it is incorrect02/17/21