For #16, it can be assume that the two angles are linear, so set them both equal to 90 (9x+x-10=90) and solve for x. Once you have x, plug it into the equations to find the measure of both angles. If both your final answers are added, they should equal 180. If not, go back and try to find where you messed up.
What you must do for this case is multiply each dimension by the reduction factor.
We have then:
For the width:
w = (15) * (0.3)
w = 4.5
For the height:
h = (10) * (0.3)
h = 3
answer:
the dimensions of the reduced picture is
w = 4.5 cm
h = 3 cm
25. yes it's direct variation
26. yes