Question 177407
Hi, Hope I can help,
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Give an ordered pair (x,y)of  numbers that satisfy the equation 

{{{ 4x-y=4 }}}
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This is a pretty easy problem
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For this problem, you just pick a number for "x", "x" can be any number
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We will use "1", now replace "x" with "1" in the equation
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{{{ 4x-y=4 }}} = {{{ 4(1)-y=4 }}} = {{{ 4-y=4 }}}, now you just solve for "y"
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We will move "4" to the right
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{{{ 4-y=4 }}} = {{{ 4 - 4 -y=4 - 4 }}} = {{{ - y = 0 }}}, to get "y" to be positive, we will multiply each side by (-1)
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{{{ - y = 0 }}} = {{{ (-1)(- y) = (-1)(0) }}} = {{{ y = 0 }}}
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{{{ x = 1 }}}
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{{{ y = 0 }}}
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You can check by replacing the letters with numbers in the equation
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{{{ 4x-y=4 }}} = {{{ 4(1)-(0)=4 }}} = {{{ 4 - 0 = 4 }}} = {{{ 4 = 4 }}} (True)
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{{{ x = 1 }}}
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{{{ y = 0 }}}
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Ordered pairs are given as ( x,y ), our ordered pair ( or point ) is ( 1,0 )
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This equation is a line, to find a line we need two points, we already have one point, let us find one more point
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{{{ 4x-y=4 }}}
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Name a number for "x", we will use (-1)
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Replace the letter with the number, {{{ 4x-y=4 }}} = {{{ 4(-1)-y=4 }}} = {{{ (-4)-y=4 }}}
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Solve for "y", {{{ (-4)-y=4 }}}, we will move (-4) to the right side
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{{{ (-4)-y=4 }}} = {{{ (-4) + 4 -y=4 + 4 }}} = {{{ -y= 8 }}}
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We will now multiply each side by (-1)
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{{{ -y= 8 }}} = {{{ (-1)(-y)=(-1)( 8) }}} = {{{ y= (-8) }}}
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{{{ x = (-1) }}}
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{{{ y = (-8) }}}
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Replace the letters with numbers in the original equation
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{{{ 4x-y=4 }}} = {{{ 4(-1)-(-8)=4 }}} = {{{ (-4) + 8 =4 }}} = {{{ 4 = 4 }}} (True)
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{{{ x = (-1) }}}
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{{{ y = (-8) }}}
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Ordered pairs are given as ( x,y ), our ordered pair, or point is (-1,-8)
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To draw the equation on a graph, you draw a line through the two points (1,0) and (-1,-8)
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Here is the graph
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{{{ drawing ( 500,500,-10,10,-10,10,grid(1), blue ( circle (1,0,0.1)), circle (1,0,0.2), blue ( circle (-1,-8,0.1)), circle (-1,-8,0.2), graph ( 500,500,-10,10,-10,10, 4x-4)) }}}
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Two points that satisfy the equation are (1,0) and (-1,-8)
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Hope I helped, Levi