All categories

2 years ago

1.3x - 10= 0.8x - 8 solve for x

Mathematics

2 answers:

Neporo4naja [7]2 years ago

5 0

Answer:

x = 4

Step-by-step explanation:

1.3x - 10 = 0.8x - 8

start by getting all like terms to the same side

subtract 0.8 x from both sides, add 10 to both sides

0.5x = 2

divide both sides by 0.5

x = 4

OverLord2011 [107]2 years ago

3 0

Answer:

x = 4

Step-by-step explanation:

1.3x - 10 = 0.8x - 8

Add 10 to both sides.

1.3x = 0.8x + 2

Subtract 0.8x from both sides.

0.5x = 2

Divide by 0.5.

x = 4.

Proof:

1.3x - 10 = 0.8x - 8

1.3(4) - 10 = 0.8(4) - 8

5.2 - 10 = 3.2 - 8

-4.8 = -4.8

You might be interested in

Find the equation of the tangent line to the curve (a lemniscate)

olya-2409 [2.1K]

Answer:

$m=\frac{9}{13}$ and $b=\frac{40}{13}$

Step-by-step explanation:

The equation of curve is

$2(x^2+y^2)^2=25(x^2-y^2)$

We need to find the equation of the tangent line to the curve at the point (-3, 1).

Differentiate with respect to x.

$2[2(x^2+y^2)\frac{d}{dx}(x^2+y^2)]=25(2x-2y\frac{dy}{dx})$

$4(x^2+y^2)(2x+2y\frac{dy}{dx})=25(2x-2y\frac{dy}{dx})$

The point of tangency is (-3,1). It means the slope of tangent is $\frac{dy}{dx}_{(-3,1)}$ .

Substitute x=-3 and y=1 in the above equation.

$4((-3)^2+(1)^2)(2(-3)+2(1)\frac{dy}{dx})=25(2(-3)-2(1)\frac{dy}{dx})$

$40(-6+2\frac{dy}{dx})=25(-6-2\frac{dy}{dx})$

$-240+80\frac{dy}{dx})=-150-50\frac{dy}{dx}$

$80\frac{dy}{dx}+50\frac{dy}{dx}=-150+240$

$130\frac{dy}{dx}=90$

Divide both sides by 130.

$\frac{dy}{dx}=\frac{9}{13}$

If a line passes through a points $(x_1,y_1)$ with slope m, then the point slope form of the line is

$y-y_1=m(x-x_1)$

The slope of tangent line is $\frac{9}{13}$ and it passes through the point (-3,1). So, the equation of tangent is

$y-1=\frac{9}{13}(x-(-3))$

$y-1=\frac{9}{13}(x)+\frac{27}{13}$

Add 1 on both sides.

$y=\frac{9}{13}(x)+\frac{27}{13}+1$

$y=\frac{9}{13}(x)+\frac{40}{13}$

Therefore, $m=\frac{9}{13}$ and $b=\frac{40}{13}$ .

5 0

3 years ago

Sunhee had four plastic shapes a square, a circle, and a pentagon in how many ways can she line up the four shapes of the circle

julsineya [31]

Answer:

only three shapes are mentioned.

But anyhow, 4 shapes allow the following reasoning...

you can start lining up with any of the for shapes, so you have 4 possibilities, for the second position you have 3 possibilities, for the third 2 and for the last only 1.

so 4*3*2*1= 24 possible ways

but with the added rule to keep the circle and the square apart, we have to reduce the number.

by the same step-by-step reasoning we get

4 possibilities for the 1st item

only 2 possibilities for the 2nd item

(if 1st is square or circle, the other one's not an option, if it's not we have to choose one of them to not place them both at point 3 and 4)

only 1 choice for the 3rd item

(reasoning as above, if 2nd is square or circle, we have to the only other, if it isn't, we can put it here at 3rd position)

plus scenarios where either square or circle are on 1st point, the other's on 4th.

I guess that makes 14 possible arrangements

5 0

3 years ago

Samuel is looking at the floor plan of his house to determine how much carpet he needs to buy for his basement. Based on the flo

DerKrebs [107]

Answer:

B) First, find two areas using (4m x 10m = 40m2) and (8m x 3m = 24m2). Next, add (40m2 + 24m2 = 64m2).

Step-by-step explanation:

Samuel should is looking to find the area of his basement in order to cover it with carpet.

An area is calculated by multiplying two dimensions (so answers A and D are not it).

Best solution is to divide the area into two large rectangles then ADD them together to get the total area.

The only scenario where he could have subtracted something based on his plan is if he would have multiplied the 10m by the 12m then subtracted the area that is not part of his basement (7mx8m). He would have achieved the same result of course, but by going a different way.

3 0

3 years ago

3raise power minus 4

balandron [24]

Answer:

1/81

Step-by-step explanation:

7 0

3 years ago

Read 2 more answers

If you had half a dollar, three quarters, eight dimes, six nickels, and nine pennies, how much money would you have altogether?

hjlf

Answer:

$1.69

Step-by-step explanation:

Half a dollar = $0.50

Eight dimes = $0.80

Six nickels = $0.30

Nine pennies = $0.09

Total = $0.50 + $0.80 + $0.30 + $0.09 = $1.69

4 0

2 years ago