Help I don't understand this math problem!!!!! 10 pts.?

Question

Explain and answer both questions please.

Write an equation of the line that passes through each point with given slope.



1.) (5,4), m= -5

2.) (5,3), m= 1/2

Answer 1

Given points (x1,y1) and (x2,y2) find the equation of the line.
Option 1
1) get the slope by m = (y2-y1)/(x2-x1).
2) pick either (x1,y1) or (x2,y2) as the point to use with your
slope.
3) follow the given point and slope steps below for the form you
want

Option 2
1) get the slope by algebraic solution of point-slope equation
(y2-y1) = m(x2-x1). (Note this already has the substitution
(x,y)=(x2,y2).)
2) pick either (x1,y1) or (x2,y2) as the point to use with your
slope.
3) follow the given point and slope steps below for the form you
want.

Given point (x1,y1) and slope m and you want point-slope form:
1) substitute values into the equation (y-y1) = m(x-x1)
2) you're done

Given point (x1,y1) and slope m and you want standard form:
Option 1
1) get point-slope equation through above steps
2) use algebra to manipulate into the form y = mx+b
3) you're done

Option 2
1) calculate the y intercept (b) by b = y1-mx1
2) directly substitute into the formula y = mx+b
3) you're done

its easy have a look the site -

One suggestion - in math, the saying No Pain No Gain is very apt :)

Answer 2

Use the general equation of a line when the slope "m" is known and a point on the line is known:
y-y1=m(x-x1)
when the point on the line is (x1, y1).

Solution to problem # 1:
Substitution into the equation gives:
y-4 = -5 (x-5)
Expanding the right side of the equation gives:
y-4 = -5x +25
Simplification gives the answer in the usual y=mx+b equation format:
y = -5x +29

Solution to problem # 2:
Substitution into the equation gives:
y-3 = (x-5)/2
Multiplying both sides of the equation by 2 gives:
2y - 6 = x - 5
Simplification gives the answer in the usual y=mx+b equation format:
y = (x + 1)/2

Answer 3

In this case, it's a simple formula -- y = mx + b

You have x, y, and m.

4 = (-5)(5) + b

4 = -25 + b

29 = b

Now, going back to the x and y...

y = -5x + 29

You use the same thing with the second question:

3 = (1/2)(5) + b

If you work through that as above, b = 1/2, and you put it together for the equation.

The form used by the others is simpler to understand when you put it together, but it's really a matter of preference. Eventually, though, you should be able to understand both.

Answer 4

you use the equation in standard form
y=mx+b m is the slope and b is the y intercept
-first plug in the slope
1. y= -5x+b
-next you will need to find the y intercept, plug in the x and y points
4= -5(5)+b
-now that you have only one unknown variable you can solve for the y-intercept or b...
4= -25+b
29=b
-plug the b and the m back into the equation
1. y= -5x+29 -this is your answer

2. y=1/2 x+b
3=1/2(5)+b
3=2.5+b
.5=b
y=1/2 x+.5 -this is your answer

Answer 5

There's a long explanation and a short explanation.
Here's the short one. Do you understand point-slope form?
See your book and study it while working on logical reasoning and number sense so you can solve tougher problems using your own intuition.

Anyways, y-y1=m(x-x1)
1)y-4=-5(x-5)
2)y-3=(1/2)(x-5)

Answer 6

so you gots your y = mx +b equation. Where b is your y intercept and m is your slope. So your cordinates are in the form (x,y) so we plug in the numbers for 1.

4 = -5*(5) + b;
and then we solve that for b... we get b = 29 so we now know enough info to make this an equation.

y = -5x + 29

and that's the answer for 1, try the other and e-mail me if you have any questions.

Answer 7

general equation is y-y1=m[x-x1]
so
y-4=-5[x-5]
y-3=1/2[x-5]