To get the x-intercept, we simply set y = 0 and solve for "x".
now, we have the slope and the y-intercept, well, let's plug those two in the slope-intercept form, reason why is called that anyway,
You are given the X value, replace x with 2 in the first equation to solve for y:
y=2x +3
y = 2(2) +3
y = 4+3
y = 7
Now replace y with 7 and x iwth 2 in the second equation and solve for k:
y = -x +k
7 = -2 +k
Add 2 to both sides:
9 = k
so k = 9
The point is given as k-2, which is 9-2 = 7, which is what y equals in the first equation.
K = 9
The magnification is 0.54
Given,
The distance between object and concave lens, u = -21 cm
Focal length of the concave lens, f = -25 cm
Let m be the magnification.
m = v/u
Here v is the position of image.
We have to find v first.
By using lens equation we can determine v.
That is,
1/f = 1/v – 1/u
So,
- (1/25) = 1/v – (-1/21)
- (1/25) = 1/v + 1/21
1/v = - (1/25) – 1/21
1/v = (-25 – 21) / (21 x 25)
1/v = - (46/525)
Therefore v = - (525/46)
v = -11.41 cm
Now we have to find magnification, m.
m = v/u
= (-11.41) / (-21)
= 0.54
Here magnification is 0.54
Learn more about concave lens here: brainly.com/question/12944945
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