Ducks have 1 head. Dogs have 1 head.
Ducks have 2 feet. Dogs have 4 feet.
If x = no. of ducks and g = no. of dogs
x + g = 25
2x + 4g = 80
Let's use substitution to solve.
x + g = 25 ⇒ x = 25 - g
replace x with 25 - g in the other equation and solve for g
2x + 4g = 80
2(25 - g) + 4g = 80
50 - 2g + 4g = 80
50 + 2g = 80
2g = 30
g = 15
Now use g = 15 in an earlier equation to find x.
x + g = 25
x + 15 = 25
x = 10
Answer:
71.25%.
Step-by-step explanation:
To find the average, we can simply add up the percentages and divide by how many there are.
We can do this by:
= 71.25%
Answer:
x > 3
Step-by-step explanation:
The only thing you need to do is just divide both sides by -7
-7x/-7<-21/-7
x>3
I hope this helped!! Good luck (:
bearing in mind that standard form for a linear equation means
• all coefficients must be integers, no fractions
• only the constant on the right-hand-side
• all variables on the left-hand-side, sorted
• "x" must not have a negative coefficient

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