The graph of the quadratic function y=2x2+5x−6 is parabola.
y=2x2+5x−6
=2(x2+2(45)x+(45)2)−2(45)2−6
=2(x+45)2−873 Vertex:(−45,−873)
y -intersection: x=0,y=2(0)2+5(0)−6=−6
Point (0,−6)
x -intersection(s): y=0,0=2(x+45)2−873
2(x+45)2=873
(x+45)2=1673
x+45=±1673
x=−45±473
x1=−45−473
x2=−45+473
Point (4−5−73,0), Point (4−5+73,0).
x=1:y=2(1)2+5(1)−6=1
Point (1,1).
x=−2:y=2(−2)2+5(−2)−6=−8
Point (−1,−9).
The graph of the linear function y=4x−3 is a straight line.
x=0:y=4(0)−3=−3 .
Point (0,−3)
y=0:0=4x−3=>x=43
Point (43,0)
Points of intersection (1,1),(−1.5,−9)
Check
2(1)2+5(1)−6=4(1)−3
1=1,True
2(−1.5)2+5(−1.5)−6=4(−1.5)−3
−9=−9,True
Solve the equation algebraically
2x2+5x−6=4x−3
2x2+5x−6−4x+3=0
2x2+x−3=0
D=(1)2−4(2)(−3)=25
x=2(2)−1±25=4−1±5
x1=4−1−5=−1.5
y1=4(−1.5)−3=−9
x2=4−1+5=1
y2=4(1)−3=1
x1=−1.5,x2=1
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