Algebra Formulas Made Easy
Please help me! Algebra 1 Confusion..?
Please, I’m begging anyone to help me. I’ve always sucked at math and I’ve been trying my hardest to learn it. I’ve been held back in math for failing. I’ve been studying over and over and can’t seem to solve certain problems. It’s even caused me to cry… i know i’m pathetic.
i know these problems are easy, which is what made me cry, but please explain to me how to do these:
Formula: y-y=m(x-x); m=slope
Problem: m=4; (-1, 1/2)
Plug in: y-1/2= 4(x+1)
Answer: Either y=4x-2/3 or y=4x+ 9/2 (only one of them is correct)
Formula: Y2 – Y1/X2-X1
Problem: (0,1)(3, -8)
Answer: Either y= -3/2x + 8 or y= -3x + 5
Please Help me
it would be greatly appreciated
Both problems can be done using a straight-forward technique.
1. Take the right formula
2. Plug the values.
3. Find the unknowns by doing proper math (the most imp. part)
Problem 1:
y-y0 = m(x-x0)
Given that m=4 and x0 = -1 and y0 = 1/2
y-1/2 = 4(x+1)
2y – 1 = 8(x+1) … Multiply by 2
2y = 8x + 8 + 1
2y = 8x + 9
y = 4x + 9/2 … Divide by 2.
y = 4x + 9/2 … ans
Problem 2:
y-y1/y2-y1 = x-x1/x2-x1 … two point equation of a line .. very useful formula where (x1,y1) and (x2,y2) are two points whose co-ordinates are known.
Given that (x1,y1) = (0,1) and (x2,y2) = (3,-8)
we get that:
y-1 / (-8-1) = x-0 / (3-0)
y-1 / -9 = x / 3
y – 1 = (x * -9) / 3 … In the next step, we divide -9 by 3 = -3
y – 1 = -3x
y = -3x + 1 .. ans
Once you understand the question correctly, I feel that you can easily do these problems. Put your mind to it and believe in yourself.
Please check for yourself since I might have made some mistakes while typing.
Hope that helps.
Algebra – Formulas – Ch. 2.2
