Answer: <em>it will actually be -3, 7</em>
19x-15 = 15x -7
4x = 8
x =2
19(2) -15 = 23
15(2) -7 = 23
In 1975 it was 1000tons, ok, well, in 1976 it went up by 10%, how much is a 10% increase?

well, in 1976 it was 1100 tons then, and in 1977 it went down by 5% of 1100, well, if we take 1100 to be the 100%, then what is a 5% decrease?
The circumference of a circle is all around the circle
The diameter is a line that crosses straight across a circle
And the radius is half the diameter :)