Answer: Todd used 27 black tiles.
Step-by-step explanation:
Let x represent the number of black tiles that Todd used.
Todd uses 21 white tiles & some black tiles to make a mosaic. This means that the total number of white and black tiles that Todd used is 21 + x
Each tile has an area of 3 square centimeters. This means that the total area covered by the white tiles is
21 × 3 = 63 square centimeters
Also, the total area covered by the black tiles is
3 × x = 3x square centimeters
The mosaic has a total area of 144 square centimeters. This means that
3x + 63 = 144
3x = 144 - 63
3x = 81
x = 81/3 = 27
Answer:
Step-by-step explanation:
Use Pythagorean theorem since you have a right triangle 
= 
225 = 100 + 
so x =
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
4 feet? 20/5=4? Not too sure
