Answer:
(x , y) = ( -4 , 1)
Step-by-step explanation:
2x + 7y = -1 --------eqn 1
4x - 3y = -19 ----------eqn 2
Step 1: let's pick eqn 1, to make y the subject of the formula
2x + 7y = -1
7y = -1 - 2x
Divide both sides by 7, to make y the subject of the formula
7y/7 = (-1 - 2x)/7
y = (-1 - 2x) / 7
Step 2: substitute y into the equation 2
4x - 3y = -19
4x - 3(-1 - 2x)/7 = -19
Open the bracket
-3 * -1 = +3
-3 * -2x = +6x
4x +( 3 + 6x)/7 = -19
LCM = 7
(28x + 3 + 6x)/7 = -19
(34x + 3)/7 = -19
Cross multiply
34x + 3 = 7 * -19
34x + 3 = -133
34x = -133 - 3
34x = -136
Divide both sides by 34,to get the value of x
34x/34 = -136/34
x = -4
Step 3: substitute x = -4 into eqn 1
2x + 7y = -1
2(-4) + 7y = -1
-8 + 7y = -1
7y = -1 + 8
7y = 7
Divide both sides by 7, to the value of y
7y/7 = 7/7
y = 1
(x , y) = ( -4 , 1)
Answer:
Length of the rectangle = 9.58 feet and width = 27.14 foot
Step-by-step explanation:
Let the length of the rectangular area is = x feet
and the width of the area = y feet
Area of the rectangle = xy square feet
Or xy = 260
y = 
-------(1)
Cost to fence the three sides = $3 per foot
Therefore cost to fence one length and two width of the rectangular area
= 3(x + 2y)
Similarly cost to fence the fourth side = $14 per foot
So, the cost of the remaining length = 14x
Total cost to fence = 3(x + 2y) + 14x
Cost (C) = 3(x + 2y) + 14x
C = 3x + 6y + 14x
= 17x + 6y
From equation (1)
C = 
Now we take the derivative,
C' = 17 - 
To minimize the cost of fencing,
C' = 0
17 - = 0
= 17
x = 9.58 foot
and y = 
y = 27.14 foot
there are the ways to reach that are conduction,convection and radiation
I hope this helps you
y=-2x
x+3.(-2x)=15
x-6x=15
-5x=15
x=-3
y=-2.-3=6
The expression 16p⁴ will be written as (2p)⁴.
<h3>What is an expression?</h3>
Expression in maths is defined as the collection of the numbers variables and functions by using signs like addition, subtraction, multiplication, and division.
Numbers (constants), variables, operations, functions, brackets, punctuation, and grouping can all be represented by mathematical symbols, which can also be used to indicate the logical syntax's order of operations and other features.
The given expression will be solved as below:-
16p⁴ = ( 2 x 2 x 2 x 2)p⁴
16p⁴ = 2⁴ x p⁴
16p⁴ = ( 2p )⁴
Therefore, the expression 16p⁴ will be written as (2p)⁴.
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