3
Simplify the expression below:
20 – 10y – 7y + 9

y = 1.705882353

Step-by-step explanation:Combine like terms: 20 + 9 = 29

29 + -10y + -7y = 0

Combine like terms: -10y + -7y = -17y

29 + -17y = 0

Solving

29 + -17y = 0

Solving for variable 'y'.

Move all terms containing y to the left, all other terms to the right.

Add '-29' to each side of the equation.

29 + -29 + -17y = 0 + -29

Combine like terms: 29 + -29 = 0

0 + -17y = 0 + -29

-17y = 0 + -29

Combine like terms: 0 + -29 = -29

-17y = -29

Divide each side by '-17'.

y = 1.705882353

Simplifying

y = 1.705882353

(0,-3) see attached graph

step-by-step explanation:

a. to solve the system, graph the two equations.

x = y+3 becomes y=x-3 has m=1/1 and b=-3. start at (0,-3) on the y-axis and plot a point. then move up 1 unit and 1 unit to the right. plot a point and connect.

y=-4x+3 has m =-4/1 and b=-3. start at (0,-3) on the y-axis and plot a point. then move down four units and to the right 1 unit. plot a point and connect.

the solution is the point (x,y) where the two lines intersect. by the graph below it is (0,-3).

b. to solve by substitution, substitute y = -4x-3 into x= y+3

x= (-4x-3) +3

x=-4x

5x=0

x=0

now substitute x = 0 back in to find y.

y= -4(0)-3

y=0-3

y=-3

solution is (0,-3)

c. use elimination by adding the equations together.

x-y=3

4x+y=-3

5x=0

x=0

then substitute into one equation to find y.

y=-4(0)-3

y=-3

b

step-by-step explanation:

a difference is the result of subtraction. while each of these expressions has subtraction in it, a difference will be the result when subtraction is the last operation applied in the order of operations for the expression. this means subtraction must be outside of the parenthesis. only b has this.