You can put this solution on YOUR website! FIRST WE FIND A COMMON DENOMINATOR FOR 4 & 18 WHICH IS 36 (2*2)(2*9) SINCE A 2 IS COMMON TO BOTH DENOMINATORS WE ONLY NEED TO USE IT ONCE. ALL OTHER NUMBERS ARE MULTIPLIED TO GET THE NEW DENOMINATOR - THUS 2*2*9=36
-3/4=X/36
4X=-108
X=-108/4
X=-27 THUS WE HAVE -3/4=-27/36
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5/18=X/36
18X=180
X=-180/18
X=-10 THUS WE HAVE -5/18=-10/36
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-27/36-(-10/36)
-27/36+10/36
-17/36