SOLUTION: A straight line crosses the x-axis at x = 3 and the y-axis at y = -4. Find the equation of the line. Please give your answer in the functional form: y = a x + b for some co

Algebra ->  Numeric Fractions Calculators, Lesson and Practice -> SOLUTION: A straight line crosses the x-axis at x = 3 and the y-axis at y = -4. Find the equation of the line. Please give your answer in the functional form: y = a x + b for some co      Log On


   

Question 73845: A straight line crosses the x-axis at x = 3 and the y-axis at y = -4. Find the equation of the line. Please give your answer in the functional form:
y = a x + b

for some constants a and b.
Answer by checkley75(3666) About Me  (Show Source):
You can put this solution on YOUR website!
(3,0)(0,-4)
THE SLOPE (m) IS
(Y2-Y1)/x2-X1)
(-4-0)/( 0-3)
-4/-3
4/3 IS THE SLOPE (m)
NOW SUBSTITUTE 4/3 FOR THE SLOPE AND THE X,Y VALUES FROM ONE SET OGF POINTD & SOLVE FOR THE Y INTERCEPT (b).
0=4/3*3+b
0=12/3+b
b=4 FOR THE Y INTERCEPT (b)
NOW WE HAVE THE FORMULA FOR THIS WHICH IS
Y=4/3X+4
+graph%28+300%2C+300%2C+-6%2C+5%2C+-10%2C+10%2C+y+=+4x%2F3+%2B4%29+ (graph 300x300 pixels, x from -6 to 5, y from -10 to 10, y = 4x/3 +4).