Would it be negative fourty (-40) as the difference between 20 and -10 is 30 so -10 minus 30 is -40 ?
You can cross multiply to get 4 * 21 = 7x
84 = 7x; divide both sides by 7
12 = x so the number 12 will go in the blank (12 girls)
Answer:
23 + 31
Step-by-step explanation:
4x+2=4x-8
2=-8
answer: no solutions