Calculus

If I read right, then r= 4.5, so that (4)(4.5)(2)-7=29

3

3x + y = 3

2x - y = -1

Add the two equations: 5x + 0y = 2 or x = 2/5 = 0.4

Substitute the value of x in the first equation: 1.2 + y = 3 so y = 3 - 1.2 = 1.8

Start with the first equation: 8=2x-6 so 14=2x so x=7

Now insert the answer for x into the second equation:

So y=2(7)-6 so y=14-6 so y=8

So at a certain point x=7 and y=8 so a coordinate would be (7,8)

a straight line with a slope of -2 and a y-intercept of 3

-2x-6 = 14

-2x = 14+6

-2x = 20

x = -10

The given equation can be simplified to 2x + 3y = 6 but that is about it.

Given 2 unknown variables (x and y) you need two independent equations to solve for them. The only other thing you can so with the above equation is to express

y in terms of x : y = (6 - 2x)/3 = 2 - 2x/3

or

x in terms of y: x = (6 - 3y)/2 = 3 - 3y/2

Both different (and possibly clumsier) ways of saying the same thing as the original equation.

7x + 13 = 2x + 3 First, subtract 3 from both sides.
7x + 13 - 3 = 2x + 3 - 3
Simplify both sides.
7x + 10 = 2x
Now, subtract 2x from both sides.
7x - 2x + 10 = 2x - 2x
Simplify again.
5x + 10 = 0
Finally, subtract 10 from both sides, simplify, and divide both sides by 5.
5x + 10 - 10 = 0 - 10
5x = -10
x = -2
So the answer is x = -2.

x - 7 - 9 = -3
x - 16 = -3
x = 13

70

(3x-2)(x-2)

It is 2.

Given f(x) = - 7x + 5x^2 + 10

So f(-2) = - 7(-2) + 5 (-2)^2 + 10 = 14 + 20 + 10 = 44

If Y = y, then it is 9y4 or 9Y4. If Y is not the same as y, then you can't simplify it any.

475

A million thousands.

1/4 * 16 = 16/4 = 4

0.8

So you have (4^(x-2))^(x+1)=15. Using a law of exponents (b^a)^c=b^(a*c) and 4=2^2, you get

4^((x-2)*(x+1))=15=2^(2(x-2)(x+1)).

Take log base two and use the rule about logs of products you get

2(x-2)(x+1)=Log_2(15)

Simplifying and substituting u for Log_2(15),

2x^2-2x-4=u, which means

2x^2-2x-(4+u)=0, using quadratic formula.

X=(1/4)(2(+or-)sqrt(4-4*2*(-4-u))) or

(1/2) plus or minus (1/4)(sqrt(36+8u))

Where sqrt(b) is the square root of b

598829

f'(x)=-3

the derivative of e is zero because its a constant. Derivative of -3x is -3. Bring the exponent of x down in front of the -3 and subtract the original exponent by 1. Ex. -3(1...which is the first exponent of the x)x^0(n-1 or 1-1=0)
all this is -3(1)x^0

x^0 is 1 so the derivative of -3x is -3

10 to the power 3 = 1000

198-22y = 220

-22y = 220-198

-22y = 22

y = 22/-22

y = -1