20,21,22,23 are the ones I need help on if you can help I’ll mark you as super smart !!!
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On 20 and 21 you have to do 120=10x-10 and solve as a linear eqaution and 6x+10= 8x+2 and solve as a linear equation for 23 you would do 4x+1+2x+3=124 I dont Know about 22 though.
Hope this helps!!