Answer: -16
Explanation:
Let the number be y
Four times a number minus twenty-one can be written as:
(4 × y) - 21 = 4y - 21
Six times the number plus eleven can be written as:
(6 × y) + 11 = 6y + 11
Combining both equations will give:
4y - 21 = 6y + 11
4y - 6y = 11 + 21
-2y = 32
y = 32/-2
y = -16
The number is -16