Find equation in slope-intercept form

  • Thread starter Thread starter gillgill
  • Start date Start date
  • Tags Tags
    Form
AI Thread Summary
The discussion focuses on finding the slope-intercept form of equations for various lines based on given points and conditions. For the line through (-2, 3/4) and (2/3, 5/2), the proposed equation y=21/32x+33/16 is questioned for accuracy. A horizontal line through (8,7) is confirmed to be y=7, indicating that the y-value remains constant. The equation for a line with an x-intercept of -2/3 and perpendicular to 2x-y=4 is debated, with the suggestion of y=-1/2x+1/3 being challenged due to incorrect y-intercept calculations. Overall, the importance of verifying equations by substituting points back into them is emphasized.
gillgill
Messages
128
Reaction score
0
find equation in slope-intercept form for line through (-2, 3/4) and (2/3, 5/2)
does y=21/32x+33/16 seem right?

find equation in slope-intercept form for line through
Horizontal, through (8,7)
is it y=7??

find equation in slope-intercept form for line with x-intercept -2/3 and perpendicular to 2x-y=4
does y=-1/2x+1/3 right?
 
Last edited:
Physics news on Phys.org
You can test your first equation by substituting the points back into your equation.

The second equation y = 7 implies that for all x values the y value are 7. Does this seem right to you?

Your last equation cannot be right since the y-intercept is not the given one!
 
Last edited:
gillgill said:
find equation in slope-intercept form for line with x-intercept -2/3 and perpendicular to 2x-y=4
does y=-1/2x+1/3 right?

On this one, I got what you did, except the y-intercept of mine was negative. When I substituted -2/3 for x in y=-1/2x, i got 0=1/3 + b, therefore moving it to the other side would yield a negative...
 
ic...thanks...
 
Thread 'Variable mass system : water sprayed into a moving container'
Starting with the mass considerations #m(t)# is mass of water #M_{c}# mass of container and #M(t)# mass of total system $$M(t) = M_{C} + m(t)$$ $$\Rightarrow \frac{dM(t)}{dt} = \frac{dm(t)}{dt}$$ $$P_i = Mv + u \, dm$$ $$P_f = (M + dm)(v + dv)$$ $$\Delta P = M \, dv + (v - u) \, dm$$ $$F = \frac{dP}{dt} = M \frac{dv}{dt} + (v - u) \frac{dm}{dt}$$ $$F = u \frac{dm}{dt} = \rho A u^2$$ from conservation of momentum , the cannon recoils with the same force which it applies. $$\quad \frac{dm}{dt}...
Back
Top