if you could help me answer multiple questions and get them correct I will donate most of my fg to you. I have to post one question at a time. so bare with me.

First q-

(5x-3)(8+x)
solve for x
x= ?

you cannot solve an expression for a variable. i assume that's an equation set equal to 0? if so, set each piece equal to 0 and isolate x

This post was edited by carteblanche on Jan 20 2015 02:25pm

this is the exact problem

^ for the first question the answer i got was 3/5, -8



This post was edited by Freebs on Jan 20 2015 03:23pm

help!!

You're correct on the first one

Second one, use exponent properties

First, multiply all of the constants together: 4*2*9 = 72

Next, u^5 times u^-3 is u^2 (same base, when multiplied, you're allowed to just add the exponents)

x^-1 times x is x^0 = 1 (x is just x^1 and 1+-1 = 0)

v^3 times v^-6 = v^-3

Slap it all together:

72*(u^2)*(v^-3) There's your answer (parenthesis only used because I can't write superscripts here)

NOTE: Negative exponents are usually frowned upon when it comes to simplifying in high school, so I would write it as 72*(u^2)/v^3 (notice I just moved the v^-3 to the bottom and switched the sign, which is another valid exponent rule)

This post was edited by Casey on Jan 20 2015 08:42pm

For a, remember that you can always add or subtract 360 degrees and end up at the same angle (since a circle has 360 degrees). So just add 360 to -267 and boom, you have your answer: 92 degrees

For b, the same thing applies. Except now just remember that there are 2*pi radians in a circle, so add or subtract (in this case we'll need to subtract since 16/3 * pi is bigger than 2*pi) 2*pi until we get something between 0 and 2pi. I had to do it twice before ending up with 4*pi/3

right yet again!

move the sqrt(2) to the other side, and we have sec(theta) = sqrt(2)

sec(theta) is basically 1/cos(theta), so take the reciprocal of each side and we have

cos(theta) = 1/sqrt(2)

Rationalize the right hand side (by that, i mean multiply top and bottom to change it into sqrt(2)/2)

So cos(theta) = sqrt(2)/2

So "the cosine of what angle will give me sqrt(2)/2)

This you just have to memorize (does "unit circle" ring any bells?)

The answers are pi/4 and 7*pi/4

Unit circle (apparently a big one) shown below for your convenience