The expression -30 + 9k and -3( 10 + 3k equivalent

Ascatterplot is produced to compare the size of a school building to the number of students at that school who play an instrument. there are 12 data points, each representing a different school. the points are widely dispersed on the scatterplot without a pattern of grouping. which statement could be true

The size of a certain cell is 2.5*10^-9m. another cell is 1.5*10^3 times larger. how large is the larger cell in scientific notation?

Idon’t understand! use slope intercept form to solve: through: (2,5) slope= undefined