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HELP WITH ALLLLL PLEASE THIS IS ALGEBRA II BTWWW:))

HELP WITH ALLLLL PLEASE THIS IS ALGEBRA II BTWWW:))-example-1
User Gill
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1 Answer

5 votes

Answer:


\textsf{23.} \quad c)\;\;y=-2x+7


\textsf{24.} \quad 12


\textsf{25.} \quad -2.33\:\:\sf (2\:d.p.)

Explanation:

Question 23

Given equation:


y=(1)/(2)x-1

If two lines are perpendicular to each other, the slopes are negative reciprocals.

Therefore, the slope of a line perpendicular to the given equation is -2.

Substitute the found slope and the given point (3, 1) into the point-slope formula to find the equation of the line:


\implies y-y_1=m(x-x_1)


\implies y-1=-2(x-3)


\implies y-1=-2x+6


\implies y=-2x+7

Question 24

Define the variables:

  • Let x = number of $20 bills.
  • Let y = number of $50 bills.

Given information:

  • Total amount cashed = $390
  • Total number of bills = 15

Create two equations with the given information:


\begin{cases}x+y=15\\20x+50y=390\end{cases}

Solve the first equation for y:


\implies y=15-x

Substitute the found expression for y into the second equation and solve for x:


\implies 20x+50(15-x)=390


\implies 20x+750-50x=390


\implies -30x+750=390


\implies -30x=-360


\implies x=12

Therefore, Kerry received 12 twenty-dollar bills.

Question 25

Given expression:


(6^2-4^2)/(-10+√(2))

Following the order of operations (PEMDAS), simplify the numerator:


\implies (36-16)/(-10+√(2))


\implies (20)/(-10+√(2))

Calculate the square root:


\implies (20)/(-10+1.414213...)

Simplify the denominator:


\implies (20)/(-8.5857864...)

Divide the numerator by the denominator:


\implies -2.3294313...

Therefore:


\implies (6^2-4^2)/(-10+√(2))=-2.33\:\: \sf (2\:d.p.)

User Fasti
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