6. the recommended heart rate for weight management exercise and improming/
cardio fitness, in beats per minute, depends on a person's age and can be
represented by the expression 0.7(220 - a).
part a: what does the variable in the expression represent?
part b: rewrite the expression using the distributive property.
part c: what is the recommended heart rate for a 20-year-old person

Part A = Age, Part B = 154 - 0.7a, Part C = 140 beats per minute (BPM)

Step-by-step explanation: The question states "...in beats per minute, depends on a person's age and can be represented..." and the variable is a, so a is age. To rewrite an expression, you need to multiply the number outside the parentheses with the terms inside the parentheses. In this case 0.7 * 220, which is 154 and 0.7 * a which is 0.7a. So the expression rewritten is 154- 0.7a. In order to solve question C you need to plug in the variable. So 0.7(220 - 20) or 154 - 0.7 * 20, whichever is easier. After solving, your answer will be 140 beats per minute.

50-38=12

step-by-step explanation:

income. 10x+1300

expenses 3x+(1800+1500)

expenses 3x+3300

to break even:

income = expense,

10x + 1300 = 3x + 3300,

solve for x.

step-by-step explanation:

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