When exercising, the maximum heart rate (r ) in beats per minute is modeled by the equation shown in the box, where (a ) represents the age of the person in years. r = 220 - a If Sanchez is 34 years old, what is his maximum heart rate?

186 beats per minute

Step-by-step explanation:

The maximum heart rate (r ) in beats per minute is modeled by the equation :

r = 220 - a ...(1)

Where

a is age of the person in years

If Sanchez age is, a = 34 years

Put a = 34 in equation (1)

r = 220 - 34

= 186 beats per minute

Hence, the maximum heart rate is 186 beats per minute.

1.)      .07x + .11y = 760
2.)        x + y=8000

we can solve the second equation for either x or y 

y= 8000 - x
or
x=8000 - y

plug 1 of those in to equation 1 (I'll use y=8000 -x)

.07x + .11(8000 -x) = 760

.07x + 880 - .11x = 760

-.04x +880 = 760

-.04x = -120

x=3000

So 3000 is invested in 7% 
     5000 is invested in 11%

Check

(3000 x .07) + (5000 x .11) = 720

210 + 550 = 760

Success!