Trig / slope help please?

Question

I do not understand these, could someone PLEASE explain them?

The angle of elevation from a point 25 feet from the base of a tree on level ground to the top of the tree is 30º. Which equation can be used to find the height of the tree?
1) tan 30º = x/25
2) cos 30º = x/25
3) sin 30º = x/25
4) 30²+25²=x²

and

The line 3x-2y=12 has:
1) a slope of 3/2 and a y-intercept of -6
2) a slope of -3/2 and a y-intercept of 6
3) a slope of 3 and a y-intercept of -2
4) a slope of -3 and a y-intercept of -6

Thank you!

I need to know how to solve it, please, I do not understand.

Answer 1

QUESTION 1:

Ask yourself: WHICH TRIG FUNCTION IS OPPOSITE OVER ADJACENT? IT IS THE TANGENT FUNCTION, RIGHT?

The bottom of the tree is 25 feet away from a point that measures 30 degrees from ground level to the top of the tree.

Answer: tan30degrees = x/25feet...choice 1.

Notice that they are NOT asking you to solve for x. Get it?

QUESTION 2:

You need to write the given equation 3x - 2y = 12 in the y =mx + b
form.

Let's do that right now.

We have:

3x - 2y = 12

I will subtract -3x from both sides of the equation.

We get:

-2y = -3x + 12...See what I did?

Next:

Divide BOTH sides of the equation by -2 to find the value of y.

We get this:

y = (-3x + 12)/-2

We can reduce the equation to this:

y = 3/2 (x) - 6

Slope is 3/2 and the y-intercept is -6.

Final answer: choice 1

Guido

Answer 2

1) tan 30º = x/25
1) a slope of 3/2 and a y-intercept of -6

Answer 3

1.equation 1 tan30*=x/25

2.-2y=-3x+12
y=3/2x-6
choice 1.
slope of 3/2 and y intercept of -6

Answer 4

The first choices are the correct answer in both problems.

Answer 5

question 1

tan30 = x/25

for question two

you'll need a graph for this. If you know how to draw this equation as a line, it's easy......... ask your dad or something.