How do I solve this equation

Answers

Answer 1

Answer: -x - y = 8
2x - y = -1

Ok, we are going to solve this in 2 parts. First we have to solve for one of the variables in one of the equation in terms of the other variable. I like to take the easiest equation first and try to avoid fractions, so let's use the first equation and solve for x.

-x - y = 8 add y to each side
-x = 8 + y divide by -1
x = -8 - y

So now we have a value for x in terms of y that we can use to substitute into the other equation. In the other equation we are going to put -8 - y in place of the x.

2x - y = -1
2(-8 - y) - y = -1 multiply the 2 through the parentheses
-16 - 2y - y = -1 combine like terms
-16 - 3y = -1 add 16 to both sides
-3y = 15 divide each side by -3
y = -5

Now we have a value for y. We need to plug it into either of the original equations then solve for x. I usually choose the most simple equation.

-x - y = 8
-x - (-5) = 8 multiply -1 through the parentheses
-x + 5 = 8 subtract 5 from each side
-x = 3 divide each side by -1
x = -3

So our solution set is

(-3, -5)

That is the point on the grid where the 2 equations are equal, so that is the place where they intersect.

Related Questions

Write a word problem that can be solved by finding the numbers that have 4 as a factor
Emily has a road map with a key that shows an Inch on the map equals 5 miles of actual distance. she will drive on two roads to get to the beach. One road is 7 inches long on the map. The other road is 5 inches long. What is the actual distance Emily will drive to the beach? Write the rule you used to find the actual distance.
Is 5 feet greater, less or equal than 60 inches?
The reciprocal of a fraction less than 1 is always a fraction greater than 1. Why is this?
The john boy peanut company produces 145 pound of peanut in day each yard they fill holds 18 ounces of peanut . Each crate they ship can hold 24 jars how many jars can they fill with one day

What is half of 750

Answers

To find half of 750, divide it by 1/2.
So,

750 ÷ 1/2

750/1 ÷ 1/2

750/2

= 375.

CROSS CHECK!

375 × 2 = 750.

half of 750 would be 375 to check just add 375 and 375

Evaluate each function at its given value

Answers

Substitution

(7)
$f(n) = 6( - 8) {}^(2) + 54( - 8) + 46$

=-2

(8)
$f(n) = - 4(7) {}^(3) + 28(7) {}^(2) - 5(7) + 40$

=5

(9)
$f(n) = 4( - 2) {}^(4) + ( - 2) {}^(3) - 9( - 2) {}^(2) + 3( - 2) - 15$

=-1

(10)
$f(a) = - 7(6) {}^(3) + 41(6) {}^(2) + 35$

=-1

(11)
$f(n) = (3) {}^(3) - 4(3) {}^(2) - 5(3) + 26$

=2

(12)
$f(x) = 2(5) {}^(2) + 7( - 5) - 30$

=-15

Hope this will help you

brennan and ilene are solving the following problem. find x, y, and z in this 45-45-90 triangle if h = 4. which of them is correct?

Answers

brennan is correct and ilene is not

What is the equation of the line that has slope -4 and passes through the point (-2,-5)

Answers

Answer:

y+5==4(x+2) this is point slope form

Step-by-step explanation:

two high speed trains are 480 miles apart and traveling towards each other. they meet in 3 hours. if one trains speed is 5 miles per hour faster than the other, find the speed of each train