Do you can posting a drawn please ?
Answer:

Step-by-step explanation:
Given the expression:

Using the distributive property: 

Simplify:

Simplify:

Therefore, the simplified given expression is, 
4 times 7 = 28
3 times 7 = 21
It will take him 21 days to make 28 bird houses.
Answer:
Valid
Step-by-step explanation:
3(x-4)=x+4 <em>Given</em>
3x-12=x+4 <em>Distribute</em>
2x=16<em> Subtract x from both sides and add 12 to both sides</em>
x=8 <em>Divide each side by 2.</em>
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