<CAD+<CDA=90
2x-y+x-1=90
3x-y=91
<CBD+<CDB=90
2x+3+y-2=90
2x+y=89
then
3x-y=91
2x+y=89
5x=180
x=36
y=17
<CDA=35
<CDB=15
5x - 20y = 60...reduce by dividing by 5
x - 4y = 12
this is the same as the other equation....therefore, it is the same line...meaning infinite solutions
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y - 7x = -14
y = 7x - 14.....slope = 7, y int = -14
7y - 49x = -2
7y = 49x - 2
y = 7x - 2/7.....slope is 7, y int is -2/7
if the slopes are the same, but the y int are different, then u have a parallel lines with no solutions
X^2-4x-5=0
according viet’s theorem
the roots are 5 and -1