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3 years ago

System of equations ( substitution methods) can someone solve these problems x=3y-5 ; x+y=3 y=x ; 3x+3y=18 y=3x+4 ; 5x-y=0

Mathematics

1 answer:

Tcecarenko [31]3 years ago

7 0

Answer:

(1,2)

(3,3)

(-1/2, 11/2)

Step-by-step explanation:

A system of equations is 2 or more equations for which the same x,y solution exists. We can solve the system in three ways: elimination, substitution, or graphing. Substitution can be used by substituting the value of one variable into the equation.

Pair x=3y-5 and x+y=3

Because x=3y-5, we can substitute 3y-5 into x in x+y=3

x+y=3

(3y-5)+y=3

3y-5+y=3

4y-5=3

4y-5+5=3+5

4y=8

y=2

We now substitute y=2 into x=3y-5.

x=3y-5

x=3(2)-5

x=6-5

x=1

Pair y=x and 3x+3y=18

Because y=x, we can substitute x into y in 3x+3y=18

3x+3y=18

3x+3x=18

6x=18

x=3

We now substitute x=3 into y=x.

y=3.

Pair y=-3x+4 and 5x-y=0

Because y=-3x+4, we can substitute -3x+4 into y in 5x-y=0

5x-y=0

5x-(-3x+4)=0

5x+3x+4=0

8x+4=0

8x=-4

x=-1/2

We now substitute x=-1/2 into y=-3x+4

y=-3x+4

y=-3(-1/2)+4

y=3/2+4

y=11/2

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3 years ago

= 2 - 4

jekas [21]

Answer:

Please find attached the required inverse of a function chart

Step-by-step explanation:

The inverse of a function is found by reversing the operations of the function

The inverse of the function f(x) = 2·x - 4 is found as follows;

x = 2·x - 4

x + 4 = 2·x

x = (x + 4)/2 = x/2 + 2

Therefore, the inverse of the function f(x) = 2·x - 4 is f(x) = x/2 + 2

The inverse function is plotted by generating data points as follows;

${}$ x ${}$ f(x)

0 2

1 2.5

2 3

3 3.5

4 4

5 4.5

6 5

7 5.5

8 6

9 6.5

10 7

11 ${}$ 7.5

12 ${}$ 8

13 8.5

14 9

15 9.5

16 10

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AVprozaik [17]

Answer:

$\large\boxed{x=\dfrac{-3+\sqrt{40+10\sqrt{10}}}{2}}$

Step-by-step explanation:

$2\log x=3-2\log(x+3)\\\\Domain:\ x>0\ \wedge\ x+3>0\to x>-3\\\\D:x>0\\============================\\2\log x=3-2\log(x+3)\qquad\text{add}\ 2\log(x+3)\ \text{to both sides}\\\\2\log x+2\log(x+3)=3\qquad\text{divide both sides by 2}\\\\\log x+\log(x+3)=\dfrac{3}{2}\qquad\text{use}\ \log_ab+\log_ac=\log_a(bc)\\\\\log\bigg(x(x+3)\bigg)=\dfrac{3}{2}\qquad\text{use the de}\text{finition of a logarithm}\\\\x(x+3)=10^\frac{3}{2}\qquad\text{use the distributive property}$

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