Find the area and perimeter of rectangle x=4.2cm. Width is x+5.8. The length is x.

Area: 42 cm²

Perimeter: 28.4 cm

Step-by-step explanation:

Simply plug in 4.2 cm for x into x + 5.8 to find the width. You width should be 10.

Area: Multiply 10 by 4.2 and you should get 42

Perimeter: Add up all the sides together (4.2 x 2 + 10 x 2) and you should get 28.4

step-by-step explanation: a reaction is first order. if the initial reactant concentration is 0.0200 m, and 25.0 days later the concentration is 6.25 x 10-4 m, then its half-life is:

the answer is b.

step-by-step explanation:

by the trigonometric ratio tangent, tangent equals opposite divided by adjacent.

therefore, tan(50) equals ac/3

multiply each side by 3 to get: ac=3tan(50)

the answer is b.