Answer:
Step-by-step explanation:
let the number be x and y
then from first condition
x - y = 3
x = y + 3
again from second condition
1/ x + 1/ y = 7 / 10
1/(y+3) + 1/y = 7 / 10
y + (y+3) = 7/ 10 y(y+3)
10(2y + 3) = 7y² + 21y
or, 7y² + 21y - 20y - 30 = 0
or, 7y² + y - 30 = 0
0r, 7y² - 14y + 15y - 30 = 0
or, ( y-2) ( 7y + 15) = 0
either
y = 2 0r -15/7
if two number are natural then two is only valid number
again from first condition
x - y =3
x - 2 = 3
x =5
Ok so the numbers are in a sequence of +3 so he would go 2,5,8,11,14. He could only have 5 groups of marbles because 2+5+8+11+14=40
x is -7
Step-by-step explanation:
21 ÷ -3 = -7
a negative times a negative equals a positive
Answer:
The leg measures 14.14 cm
Step-by-step explanation:
The "40 - 40 - 90" special right triangle is an isosceles right triangle because two angles measures the same. (Check the picture)
The legs are the same.
The hypotenuse is:
a × √2
From the question, the length of the hypotenuse is 20 cm.
20 = a × √2
20 ÷ √2 = a
a = 10√2 ≈ 14.14 cm
