Answer:
range of scores on final exam student get B is 90 to 100
Step-by-step explanation:
given data
Psychology 101 score = 66
average of his midterm = between 78 and 90
maximum = 100 points
to find out
range of scores on final exam student get B
solution
we consider here lowest marks need in final = x
so average at two marks should be
equation is
average marks = 0.5 × ( mid term marks + final marks ) .................1
put here value
78 = 0.5 × ( 66 + x )
x = 90
and
90 = 0.5 × ( 66 + x )
x = 114
so range 90 to 114
but maximum marks is 100 so
range of scores on final exam student get B is 90 to 100
The tangent line to <em>y</em> = <em>f(x)</em> at a point (<em>a</em>, <em>f(a)</em> ) has slope d<em>y</em>/d<em>x</em> at <em>x</em> = <em>a</em>. So first compute the derivative:
<em>y</em> = <em>x</em>² - 9<em>x</em> → d<em>y</em>/d<em>x</em> = 2<em>x</em> - 9
When <em>x</em> = 4, the function takes on a value of
<em>y</em> = 4² - 9•4 = -20
and the derivative is
d<em>y</em>/d<em>x</em> (4) = 2•4 - 9 = -1
Then use the point-slope formula to get the equation of the tangent line:
<em>y</em> - (-20) = -1 (<em>x</em> - 4)
<em>y</em> + 20 = -<em>x</em> + 4
<em>y</em> = -<em>x</em> - 24
The normal line is perpendicular to the tangent, so its slope is -1/(-1) = 1. It passes through the same point, so its equation is
<em>y</em> - (-20) = 1 (<em>x</em> - 4)
<em>y</em> + 20 = <em>x</em> - 4
<em>y</em> = <em>x</em> - 24
Negative 10 and positive 10
4.1 rounded to the nearest ones is 4
