Answer:
84x^10
Step-by-step explanation:
The coefficients multiply, and the exponents add.
(4x)( -3x^6)(-7x^3) = (4)(-3)(-7)x^(1+6+3) = 84x^10
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The rule for exponents is ...
(x^a)(x^b) = x^(a+b)
12(2+7)
12 is the GCF for 24 with 12 x2 =24 and 12 is the GCF for 84 with 12 x7= 84.
Make a proportion:

Then cross multiply and divide to solve.
20x=119
x=5.95
The answer is $5.95