Mary’s sister is 7 years older than Mary. Their combined ages add up to 35. How old is Mary

Mary - 14

Mary's sister - 21

Step-by-step explanation:

Let x be the age of Mary = x

age of Mary's sister = x + 7

Add up to 35

x + x + 7 = 35

2x = 35 - 7

2x = 28

2x/2 = 28/2

x = 14

Now substitute the value of x

Mary = 14

Mary's sister = 14 + 7 = 21

21 + 14 = 35

3 ft

step-by-step explanation:

since the triangle is right use pythagoras' identity to solve for a

the square on the hypotenuse is equal to the sum of the squares on the other two sides, that is

a² + 8² = ( )²

a² + 64 = 73 ( subtract 64 from both sides )

a² = 9 ( take the square root of both sides )

a = = 3

the answer is c: divide the arc's degree measure by 360°, then multiply by the circumference of the circle.