Answer:
Option A. 
Step-by-step explanation:
Let
y -----> the height of fudge brownies in centimeters
x ----> teaspoons of baking powder
step 1
Find the slope
The formula to calculate the slope between two points is equal to
take the points
(5,2.15) and (6,2.43)
substitute the values
step 2
Find the equation of the line in point slope form

we have

substitute

Isolate the variable y



Cos
θ
=
√
5
3
or it could be cos
θ
=
√
5
−
3
Explanation:
Since sin
θ
is negative, it can be in the third or fourth quadrant
Drawing your right-angled triangle, place your
θ
in one of three corners. Your longest side will be 3 and the side opposite the
θ
will be -2. Finally, using Pythagoras theorem, your last side should be
√
5
Now, if your triangle was in the third quadrant, you would have
cos
θ
=
√
5
−
3
since cosine is negative in the third quadrant
But if your triangle was in the fourth quadrant, you would have
cos
θ
=
√
5
3
since cosine is positive in the fourth quadrant
The angle immediately below x makes up the third angle of the isosceles triangle whose base angles are 55°. That third angle and x are "vertical" angles, hence equal. The value of x can be found from the sum of angles of a triangle:
x + 55° + 55° = 180°
x = 70°
The appropriate choice is the 2nd one:
70°