Find the points on the x-axis which are at a distance of 2√5 from the point (7,- 4). How many such points are there?
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Answer:
Step-by-step explanation:
let coordinates of the point=(x,0)(as the poin lies on x axis)
x1=7. y1=-4
x2=x. y2=0
distance between 2 pts=√(x2-x1)^2+(y2-y1)^2
A/Q.....
2√5=√(x-7)^2+(0-(-4))^2
on squaring both sides....
20=x^2+49-14x+16
20=x^2+65-14x
0=x^2-14x+45
0=x^2-9x-5x+45
0=x(x-9)-5(x-9)
0=(x-9)(x-5)
x-9=0. x-5=0
x=9. x=5
therefore x=9,5
and coordinates of points.....(9,0)or(5,0)
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