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marisa08231
whats the equation and i can help

ReesePantz
A= hb÷2
21=(x*(x+1))÷2
Just try all the choices out to get a total of 21.
=(3*(3+1))÷2
=(3*4)÷2
=12÷2 =6≠21

=(6*(6+1))÷2
=(6*7)÷2
=42÷2 =21
The answer is B. 6