To solve this problem, let us first assign some
variables. Let us say that:
x = pigs
y = chickens
z = ducks
From the problem statement, we can formulate the
following equations:
1. y + z = 30 --->
only chicken and ducks have feathers
2. 4 x + 2 y + 2 z = 120 --->
pig has 4 feet, while chicken and duck has 2 each
3. 2 x + 2 y + 2 z = 90 --->
each animal has 2 eyes only
Rewriting equation 1 in terms of y:
y = 30 – z
Plugging this in equation 2:
4 x + 2 (30 – z) + 2 z = 120
4 x + 60 – 2z + 2z = 120
4 x = 120 – 60
4 x = 60
x = 15
From the given choices, only one choice has 15 pigs. Therefore
the answers are:
She has 15 pigs, 12 chickens, and 18 ducks.
Answer:
627square inches
Step-by-step explanation:
Area of the composite figure.. = area of triangle + area of parallelogram
Since the triangle is an equilateral triangle;
Area of the triangle = r²sintheta
Area of the triangle = 18²sin60
Area of the triangle = 324sin60
Area of the triangle = 324(0.8860)
Area of the triangle = 280.584 square in
Area of the triangle = 281 square inches
Area of parallelogram = absintheta
Area of parallelogram = 20(20)sin60
Area of parallelogram = 400(0.8660)
Area of parallelogram = 346.4square inches
Area of parallelogram = 346 square inches
Area of the figure = 346 + 281
Area of the figure = 627square inches
5,12,13
5X5=25
12X12=144
25+144=169
answer: square root 169=13