No hablo expanol

7(z+2)-3z=44
7z+14-3z=44
7z-3z+14=44
4z+14=44
-14 -14
4z+14-14=44-14
4z+0=30
4z=30
1/4 1/4
(4z)/4=30/4
(4/4)z=15/2
1z=15/2
z=15/2

z=15/2

5 0

3 years ago

I need to solve for x and y. Any help is greatly appreciated! Thank you!

Inessa05 [86]

x=-3, y=1

Step-by-step explanation:

Given equations are:

2x-3y=-9 Eqn 1

x+y = - 2 Eqn 2

From eqn 2:

$x=-y-2$

Putting x=-y-2 in eqn 1

$2(-y-2)-3y=-9\\-2y+4-3y=-9\\-5y-4=-9\\Adding\ 4\ on\ both\ sides\\-5y-4+4=-9+4\\-5y=-5\\Dividing\ both\ sides\ by\ -5\frac{-5y}{-5}=\frac{-5}{-5}\\y=1\\Putting\ y=1\ in\ eqn\ 2\\x+1=-2\\Subtracting\ 1\ from\ both\ sides\\x+1-1=-2-1\\x=-3$

Hence,

x=-3, y=1

Keywords: Linear equations, Variables

Learn more about linear equations at:

#LearnwithBrainly

3 0

3 years ago

A pharmacist has 80 milileters of a 25 percent saline solution. Which expression can be used to find the percentage of the conce

Thepotemich [5.8K]

Answer:

Step-by-step explanation:

Final concentration % = [grams of salt / mililiters of solution] * 100

grams of salt = grams of salt from solution 1 + grams of salt from solution 2

grams of salt from solution 1 = mililiters * %/100 = 80 mililiters * 0.25 g/mililiters = 20 g

grams of salt from solution 2 = mililiters *%/100 = x*0.10 g/mililiters = 0.1x

mililiters of final solution = mililiters from solution 1 + mililiters from solution 2

mililiters of final solution = 80 mililiters + x mililiters

=> Final concentration, % = [0,10x + 20 g] / [x + 80 mililiters] * 100

6 0

3 years ago