Answer:
x = 30
Step-by-step explanation:
15 = 1/2x
multiply both sides of equation by 2
30 = x
Answer:

Step-by-step explanation:

It seems this system of equations would be solved easier using the elimination method (the x and y values are lined up).
Multiply everything in the first equation by -2 (we want the 4x to be able to cancel out with a -4x).

Now line up the equations (they are already lined up - convenient) and add them from top to bottom.

The -4x and 4x are opposites, so they cancel out.
Adding 6y and 2y gives you 8y, and adding -12 and 4 gives you -8.

Divide both sides by 8.

Since you have the y-value you can substitute this in to the second (or first equation, it doesn't necessarily matter) equation.

Simplify.

Add 2 to both sides.

Divide both sides by 4.

The final answer is
.

Answer:
bxjzjjxhx
Step-by-step explanation:
zjjxjxbz1+1+1++1+1++1
The point (2, 5) is not on the curve; probably you meant to say (2, -5)?
Consider an arbitrary point Q on the curve to the right of P,
, where
. The slope of the secant line through P and Q is given by the difference quotient,

where we are allowed to simplify because
.
Then the equation of the secant line is

Taking the limit as
, we have

so the slope of the line tangent to the curve at P as slope 2.
- - -
We can verify this with differentiation. Taking the derivative, we get

and at
, we get a slope of
, as expected.