Answer:

Step-by-step explanation:
Area = Length × Width
→ Identify the length and width
Length = 5 and Width = 3
→ Substitute in the values
Area = 5 dm × 3 dm
→ Convert into cm
Area = 50 cm × 30 cm
→ Simplify
1500 cm²
Answer:
Height of the lamppost = 5.602 ft + 2.912 ft = 8.514 ft
Step-by-step explanation:
The illustration form a triangle that can be demarcated into 2 right angle triangle. One triangle representing depression triangle and the other elevation triangle.
Depression triangle
The opposite side of the triangle formed is the length of the pole from the base to the horizontal line of sight. Therefore,
using tangential ratio
tan 35° = opposite/adjacent
tan 35° = a/8
cross multiply
a = 8 tan 35°
a = 8 × 0.70020753821
a = 5.60166030568
a = 5.602 ft
Elevation triangle
The opposite side of this right angle triangle represent the length from the horizontal line of sight to the top of the lamppost.
tan 20° = opposite/adjacent
tan 20° = b/8
cross multiply
b = 8 tan 20°
b = 8 × 0.36397023426
b = 2.91176187413
b = 2.912 ft
Height of the lamppost = 5.602 ft + 2.912 ft = 8.514 ft
The lengths of the rectangles are 7 and 12 respectively. Form the ratio 7/12. The widths of the rects. are x and 5 respectively. Form the ratio x/5. Now equate these two ratios:
7 x
--- = ---
12 5
Solve this for x. One way to do this would be to cross-multiply, obtaining 12x = 35, and solving this result for x. x will be a fraction. Write the numerator and denominator in the boxes given.
Note: In option A, it should be "+" instead of "(".
Given:
The expression is

To find:
The equivalent expression.
Solution:
We have,

Using distributive property, we get


On combining like terms, we get


The expression
is equivalent to the given expression.
Therefore, the correct option is A.
A) 2x + 10 equals 2x + 10
B) 7x + 3 does NOT equal 7x + 15
C) 4y - 8 doe NOT equal 4y - 2
D) 2y + 12 does NOT equal 2y - 12
Thus, A is the appropriate answer.
Hope that helped!