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Can anyone please do these input an attachment in i did some of the questions but ion know how to do the rest pleasee i need to turn it in asappp‍♀️

Can anyone please do these input an attachment in i did some of the questions but-example-1
User Gering
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1 Answer

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Answer:

Question 3



(a)\quad\boxed{\displaystyle y= -(2)/(3)x + b}


(b)\quad\boxed{y = (3)/(2)x + b}

Question 4


(a) \quad \boxed{40 x^8}


(b)\quad \boxed{3x^2-x-44}


(c) \quad\boxed{\quad 5x^2-6x+10xy-2y+1\quad}


(d) \quad \boxed{3x^3-3x^2 -3x +89}

Explanation:

Question 3

Part a

The given line has an equation

y = -(2)/(3)x - 5 \cdots\cdots[1]


\rm{The \: slope\: of \: this\: line =} \displaystyle -(2)/(3)

(a) Equation of a parallel line
All lines parallel to the given line [1] will have the same slope

So equation of a line parallel to [1] would be

\boxed{\displaystyle y= -(2)/(3)x + b}
where b is the y-intercept.

We cannot determine the y-intercept unless we are given a point through which the parallel line passes, so leave it as is

Part b

Perpendicular lines will have a slope which is the negative of the reciprocal of the line given in [1]


\sf{Reciprocal \;of \displaystyle -(2)/(3) = -(3)/(2)}\\\\\sf{Negative \; of\;the \;reciprocal\;= \displaystyle -\left(-(3)/(2)\right) = (3)/(2)
So a perpendicular line will have the equation

\boxed{y = (3)/(2)x + b}

Again, b cannot be determined unless we are given a point through which the line passes

Question 4

Part a


4x^3\left(10x^5\right) = 4\cdot 10 \cdot x^3(x^5) \\ \\= 40(x^(3 + 5))\\\\= \boxed{40 x^8}

Part b


\left(3x\:+\:11\right)\left(x\:-\:4\right)

use the FOIL method (first-outer-inner-last) to multiply
First terms in both are 3x and x so for F we get
\large \text{$ 3x \cdot x = 3x^2 $}
Outer terms are 3x and - 4; multiply to get 3x × (-4) =
-12x

Inner terms are 11 and x; multiply to get
11x

last terms are 11 and -4; multiply to get
-44

So the result is


3x^2-12x+11x-44

= \boxed{3x^2-x-44}

Part c


\left(x\:+2y\:-\:1\right)\left(5x\:-\:1\right)

We can rewrite this as

5x(x + 2y - 1) -1(x + 2y - 1)\\\\= 5x(x) +5x(2y) -5x(1) -1(x) - 1(2y) -1(-1)\\\\= 5x^2 + 10xy -5x -1x -2y + 1\\\\= 5x^2 + 10xy - 6x -2y + 1

We usually write this in decreasing powers of x followed by the y terms and then the constants to get


\boxed{\quad 5x^2-6x+10xy-2y+1\quad}

Part d


3x\left(x^2-5\right)-\left(3x^2-12x\:+\:11\right)+\:100

Expand individual terms and then add everything together and simplify if necessary


3x\left(x^2-5\right) = 3x(x^2) -3x(5) = 3x^3 -15x\\

-(3x^2 - 12x + 11) = -3x^2-(-12x) -(11) = -3x^2 + 12x - 11

Adding all the terms and adding the constant 100 gives us:

3x^3-15x -3x^2 + 12x - 11 + 100

Gather like terms and simplify:

3x^3 -3x^2 -15x + 12x -11 + 100\\\\


= \boxed{3x^3-3x^2 -3x +89}

User Jhedstrom
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