3x + y = 19 , and x + 3y = 1.
find the value of 2x + 2y
can anyone explain this one for me?

The value of 2x + 2y = 10

One variable linear equation is an equation that has a variable and the exponent number is one.

Can be stated in the form:

or

ax + b = c, where a, b, and c are constants, x is a variable

Whereas the two-variable linear equation is a linear equation that has 2 variables and the exponent is one

Can be stated in the form:

x, y = variable

3x + y = 19, and x + 3y = 1

The two equations above are equation 2 variables

Can be solved by elimination and substitution

3x + y = 19 x1 ---> 3x + y = 19

 x + 3y = 1 x3 ----> 3x + 9y = 3

                                 ---------------- -

                                       -8y = 16

                                          y = -2

x + 3 (-2) = 1

x -6 = 1

x = 7

We input both x and y values to solve the equation:

2x + 2y

2 (7) +2 (-2)

= 14-4

= 10

the slope-intercept form of the linear equation

link

a graph of a linear equation

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system of linear equations

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answer: the first one

step-by-step explanation: use a calculator and divide the minutes by the dollars.

the value of v.w= -12.

step-by-step explanation:

we are given three vector r,v and w as:

r = < 5, -5, -2> ; v = < 2, -8, -8> ; w = < -2, 6, -5>

we know that r,v and w could also be represented as:

r=5i-5j-2k

v=2i-8j-8k

and w= -2i+6j-5k

where i,j and k are the unit vectors of x,y and z-axis respectively.

also we know that it has the following property:

i.i=1 ; j.j=1; k.k=1

and i.=j.i=i.k=k.i=j.k=k.j=0

i.e. when we multiply two vectors or we find it's dot product we need to only multiply the components of x coordinates with each other; y with each other and z with each other.

hence, v.w= (2i-8j- -2i+6j-5k)

                  = 2×(-2)+(-8)×(6)+(-8)×(-5)

                  = -4-48+40

                  = -12

hence, v.w= -12