What is the equation of a line that passes through (-5, 0) and (4,18) in slope-intercept form?

What is the simplified form of (3.25x10^3)(7.8x10^6) written in scientific notation?

Atriangular field has sides of lengths 21, 39, and 41 yd. find the largest angle. (round your answer to the nearest degree.)

This is a map of the mars exploration rover opportunity predicted landing site on mars. the scale is 1cm : 9.4km. what are the approximate measures of the actual length and width of the ellipse? i mostly need to know how to set it up : )