Combine like terms to simplify the expression: 1.3b+7.8−3.2b

The equation a = $\frac{1}{2}(b_1 + b_2 )h$ can be used to determine the area , a, of a trapezoid with height , h, and base lengths, $b_1$ and $b_2$ . Which are equivalent equations?

(a) $\frac{2a}{h} - b_2 = b_1$

(b) $\frac{a}{2h} - b_2 = b_1$

(c) $\frac{2a - b_2}{h}$ = $b_1$

(d) $\frac{2a}{b_1 + b_2} = h$

(e) $\frac{a}{2(b_1 + b_2)}$ = h

Answer: (a) $\frac{2a}{h} - b_2 = b_1$ ; (d) $\frac{2a}{b_1 + b_2} = h$ ;

Step-by-step explanation: To determine $b_1$ :

a = $\frac{1}{2}(b_1 + b_2 )h$

2a = ( $b_1 + b_2$ )h

$\frac{2a}{h} = b_1 + b_2$

$\frac{2a}{h} - b_2 = b_1$

To determine h:

a = $\frac{1}{2}(b_1 + b_2 )h$

2a = $(b_1 + b_2)h$

$\frac{2a}{(b_1 + b_2)}$ = h

To determine $b_2$

a = $\frac{1}{2}(b_1 + b_2 )h$

2a = $(b_1 + b_2)h$

$\frac{2a}{h} = (b_1 + b_2)$

$\frac{2a}{h} - b_1 = b_2$

Checking the alternatives, you have that $\frac{2a}{h} - b_2 = b_1$ and $\frac{2a}{(b_1 + b_2)}$ = h, so alternatives A and D are correct.

4 0

3 years ago

If a circle has a diameter of 30 meters, which expression gives its area in

sattari [20]

Answer:

C. 15²π

General Formulas and Concepts:

Pre-Algebra

Order of Operations: BPEMDAS

Brackets
Parenthesis
Exponents
Multiplication
Division
Addition
Subtraction

Left to Right

Geometry

Diameter: d = 2r
Area of a Circle: A = πr²

Step-by-step explanation:

Step 1: Define

d = 30 m

Step 2: Find Area

Substitute [D]: 30 m = 2r
Isolate r: 15 m = r
Rewrite: r = 15 m
Substitute [AC]: A = π(15 m)²
Rearrange: A = 15²π

3 0

3 years ago

Which situation represents the greatest percent of change?

ra1l [238]

The answer is B!!!!!

5 0

3 years ago