All categories

1 year ago

Which of the following represents a valid first step to solving this system of equations using the substitution method?

Mathematics

1 answer:

Phoenix [80]1 year ago

7 0

Answer:

2(2y - 1) - y = 7

Step-by-step explanation:

I guess the 2 equations are

2x - y = 7

x = 2y - 1

substitution message that you use one equation to express one variable by the other, and then you use that in the other equation to get one equation for one variable. then you solve for that, and use that result in the first equation to since for the second variable.

the equations are already defined that way, that the second equation directly defines x as an excision of y.

so, this needs to be used then in the first equation.

and that makes

2(2y - 1) - y = 7

the correct first step.

You might be interested in

Evaluate the function at x = –2.

MrRissso [65]

Y=3
..............................

8 0

2 years ago

Katie is getting her laundry done it cost $2.25 per square foot of flowers added to the yard if she wants 12.4 ft.² of flowers h

7nadin3 [17]

Answer:

Katie needs to pay $27.9.

Step-by-step explanation:

Given;

Cost of per foot = $2.25

Number of flowers in her yard = 12.4 square foot

We need to find how much she needs to pay.

Solution:

Now we know that;

$1\ ft^2 = \$2.25$

So for $12.4 ft^2$ = Cost for $12.4 ft^2$ .

By using Unitary method we get;

Cost for $12.4 ft^2$ = $2.25\times12.4= \$27.9$

Hence Katie needs to pay $27.9.

5 0

2 years ago

The perimeter of a rectangle is 20.2 CM and it's area is 24.4 cm squared what is its length and width

erma4kov [3.2K]

Answer:

Length of Rectangle = 4 cm And

Width of Rectangle = 1.9 cm

Step-by-step explanation:

Given as :

The perimeter of rectangle = 20.2 cm

The area of rectangle is 24.4 cm

Let the length be L

And width be w

Now Area of rectangle = Length × width

Or, 24.4 = L × W

And Perimeter = 2 (Length + Width ) = 2 (L + W )

Or, 20.2 = 2(L + W )

Or , L + W = 10.1 cm ............ 1

Now, (L - W )² = (L + W)² -4 LW

Or, (L - W )² = ( 10.1)² -4 (24.4)

I.e (L - W )² = 4.41

Or , L - W = 2.1 cm .............. 2

SO , From 1 and 2

( L + W) + (L - W) = 10.1 cm - 2.1 cm

Or, 2L = 8

∴ Length = 4 cm

Again , Width = 4 cm - 2.1 cm = 1.9 cm

Hence Length of Rectangle = 4 cm And

Width of Rectangle = 1.9 cm Answer

6 0

2 years ago

What is the slope of this line? A. 1/3 B. 1/2 C. 1 D. 2

HACTEHA [7]

Slope = rise / run

so answer is

C. 1

6 0

2 years ago

Read 2 more answers

Evaluate 3x2 – 3y3 when = 4 and y = 3

marysya [2.9K]

Answer:

24 - 27 (answer would be -3)

Step-by-step explanation:

5 0

2 years ago