Quick Homework Help

# Does anyone know a handy memory trick for remembering how to solve for slope and y-intercept? Also I've forgotten the formula for slope. Could someone remind me? ⚑ Flag

by Reasonz at June 14, 2010

You need to solve for y first.  Since there are 2 variables, I tell my students to circle the y so they focus on that. The generic slope intercept form is:  y = m x + b One day my students asked me why did they use the letter m for slope and b for the y-intercept..... I drew an equilateral triangle around the m... it them looked like a Mountain....  and motains have slopes!  If you go 'up' the mountain from left to right, then it is a positive slope.... going down the mountain from L-R is a negative slope, and the bottom of the mountain (base of the triangle) I put a big circle on it for the bear cave.... that is a slope of zero. The 'b' I draw sloppy.... the down stroke reminds me that it is the y axis....  the circle loop reminds me of a circled point on the y-axis.... the y-intercept!  This is the point where the graph crosses the y-axis. How's that??

Hartman June 14, 2010

PS - Slope is Rise/Run                    = Change in y/ Change in x                   = (y2-y1) / (x2-x1)     (numbers being subscripts)

Hartman June 14, 2010

Slope formula = change in y/change in x. Remember: if the line rises to the right the slope is +, but if it rises left the slope is -.For the rest of your question: you can only solve for 1 missing variable at a time, so, first make sure the x & y spots are filled. If not, put in the coordinates you were given. Then to find the y-int (i.e. the place where the line crosses the y-axis so x=0), just let x=0 in the equation and out will pop the value of y.To find the slope (m) in the equation, sub the given y intercept into the b slot. Rearrange to m= form and you'll have it. Good luck!

suehellman June 14, 2010

Slope is rise/run.  You run up a mountain, and a steep slope goes very high, while a gentle slope doesn't go as high that quickly.  For the y-intercept, you make x = to zero and the remaining answer is your y-intercept.y = mx + bm = slope; b = y-intercept

yankeekid June 14, 2010