All categories

3 years ago

I need help asap with math

Mathematics

1 answer:

Dmitrij [34]3 years ago

4 0

I'm not even going to bother with the substitution method.
Instead of all that, I just want to show you something:

Take the FIRST equation:

y - 2x = 8
Add 2x to
each side: y = 8 + 2x

Multiply each
side by 2 : 2y = 16 + 4x

Look at that ! The first equation says the same thing as the second one !
Both of them are actually the same equation.
You actually have only one equation, with 'x' and 'y' in it.
If you graph it, the graph is a straight line, and EVERY point
on the line is a solution of the equation.

==> There are an infinite number of solutions, because
they only gave you one equation, with two unknown variables.
To find a unique solution, you'd need two equations.

You might be interested in

This is the other part of the question that I need help on.

coldgirl [10]

7x+(x+20)=180
Just simplify. Hope this helped:)

4 0

3 years ago

X^2-15x-108 Factoring need help

sveticcg [70]

x=15-657/2=15-373/2=-5.316

x=15+657/2=15+373=20.316

3 0

3 years ago

rancher wants to fence in an area of 2000000 square feet in a rectangular field and then divide it in half with a fence down the

zheka24 [161]

Answer:

7000ft

Step-by-step explanation:

let's break down 2,000,000 into its multiples,

Multiples of 2,000,000= 2⁷ × 5⁶

Using above values to find different combinations of length(l) and breadth (b) of rectangle and corresponding parameter of rectangle

l=5, b=400,000 ,parameter= 2(5) + 2(400,000)= 800,010, total length of fence required= parameter+ side with shortest length= 800,015

l=2 b=1,000,000 parameter= 2,000,004, shortest fence required= 2,000,008

l=4, b= 500,000 parameter= 1,000,008, shortest fence required= 1,000,012
From above, we can see a trend that the parameter of rectangle decreases if length and breadth are increased provided that area is constant. So, a rectangle will have shortest parameter if all of its sides are equal.
length of side of rectangle with shortest possible parameter= 2^3 ×5^3= 1000 and breadth of side of rectangle with shortest possible parameter= 2^4× 5^3=2000
Shortest possible length of fence= 2(2000)+2(1000)+1000=7000ft

4 0

3 years ago

Read 2 more answers

Find two positive real numbers whose product is a maximum. (enter your answers as a comma-separated list.) the sum of the first

Vladimir [108]

the sum of the first and three times the second is 54.

x + 3y = 54

3y = 54 - x

y= 54 /3 - x / 3 = 18 -x /3

xy = x (18 -x /3) = 18x - x^2 / 3 = - 1/3 x ^ 2 + 18 x


since a<0, it is concave downward, and the vertex is the maximum value. That vertex occurs at x= - b /2a = (-18) / (-2/3) = 12


The first number is x=12.
The second is y = 18 -x /3 = 18- 12/ 3 = 18 - 4 = 14

5 0

3 years ago

$10 000 is borrowed at 10.5% per annum interest. How much interest is owed at the end of the first 10 months?

Leviafan [203]

Answer:

$875 is the interest owed at the end of the first 10 months

Step-by-step explanation:

In this question, we are to calculate how much interest is owed in the first ten months.

There are several routes to this but the one i will like to use is as follows.

we shall calculate the amount owed for a year, afterwards we did use this amount by 12 since there are 12 months in a year. Now we multiply whatever answer we have by 10 to get the amount owed in 10 months.

To calculate the interest, we use the simple interest formula.

Mathematically;

I = PRT/100

where P is the amount borrowed which is $10,000

R is the interest rate which is 10.5% per annum

T is the time which we agreed we would be using 1 year first.

I = (10,000 * 10.5 * 1)/100 = $1050

This is the amount in 12 months. In a single month, this will be 1050/12 = $87.5

This amount in 10 months will be 87.5 * 10 = $875

8 0

2 years ago