- x+4=-3x + 8 multi-step equations

Mathematics

2 answers:

TiliK225 [7]3 years ago

8 0

Answer:

x = 2

Step-by-step explanation:

Isolate the variable, x. Note the equal sign, what you do to one side, you do to the other. Do the opposite of PEMDAS.

PEMDAS =

Parenthesis

Exponents (& Roots)

Multiplication

Division

Addition

Subtraction

& is the order of operation.

------------------------------------------------------------------------------------------------------

First, add 3x and subtract 4 from both sides:

-x (+3x) + 4 (-4) = -3x (+3x) + 8 (-4)

-x + 3x = 8 - 4

Simplify. Combine like terms:

3x - x = 8 - 4

2x = 4

Isolate the variable, x. Divide 2 from both sides:

(2x)/2 = (4)/2

x = 4/2

x = 2

x = 2 is your answer.

Tamiku [17]3 years ago

5 0

Step-by-step explanation:

this is answer

$- x + 3x = - 4 + 8 \\ 2x = 4 \\ x = \frac{4}{2} \\ x = 2x = 2x = 2$

You might be interested in

the length of a soccer pitch is 20 m less than twice its width. the area of the pitch is 6000m^2. find its dimensions.

Setler79 [48]

X=width of a coccer pitch
2x-20=length of a soccer pitch
Area (rectangule)=length x width
We suggest this equation:
x(2x-20)=6000
2x²-20x=6000
2x²-20x-6000=0
x²-10x-3000=0
We solve this quadratic equation:

x=[10⁺₋√(100-4*1*-3000)]/2=[10⁺₋√(100+12000)]/2=
=(10⁺₋110)/2
we have two solutions:
x₁=(10-110)/2=-50, invalid solution.
x₂=(10+110)/2=60

x=60
2x-20=2(60)-20=120-20=100

Solution: the length is 100 m, and the width is 60 m.

To check:
Area=100 m*60 m=6000 m²
The twice of width is =2(60 m)=120 m,
20 m less than twice its width is: 120 m-20 m=100 m=the length.

8 0

3 years ago

Katie is buying souvenir.gifts for her big family back home. She wants to buy everyone either a key chain or a magnet. The magne

NikAS [45]

The total number of gifts = x+y.
The inequality is:
$x+y \geq 24$

Key chains cost $1, Magnets $0.50
Total Cost = x + 0.5y
Inequality is:
$x+0.5y \leq 20$

Without graphing you can solve system by using substitution:
$y = 24 - x \\ \\ x + 0.5(24-x) = 20 \\ \\ 0.5x +12 = 20 \\ \\ x = 16 \\ \\ y = 24-16 = 8$

This is one solution where the maximum x value is given.
So the most keychains that can be purchased is 16. However, because magnets are cheaper, more can be purchased as long as cost remains under 20.

If you solve both inequalities for "y", you get the upper and lower bounds for how many magnets can be purchased given a quantity of keychains.

$24-x \leq y \leq 40 -2x \\ \\ x \leq 16$

This is complete solution which gives all possible combinations.
(Graph is Attached)