Please help thank you

Yvaries directly as x. y =90 when x=6. find y when x=13

Write the slope intercept equation for line ab.

Which equation could represent the relationship shown in the scatter plot? y=−3x−2 y=−3/4x+10 y=−2/3x+1 y=9x−12 scatter plot with x axis labeled variable x and y axis labeled variable y. points go from upper left to lower right.