number 5 is not and number 7 is a function because every input has exactly one output
You should write a 1 because I f what you add is 11, 12, 13, 14, 15, 16, 17, 18, or 19 there is a 1 in the front of the numbers so you must put a 1 but if the number was 76 the number in the front is 7 so you would put 7 on the tens column.
The rule for negative exponents is that if the exponent is negative to begin with, in order to make it negative, you put it into the denominator of a fraction, and raise it to whatever the power is. To go from positive exponents (those that are already in the denominator), move it up to the numerator and make the exponent negative. So your solution would be 5x^-2
You can substitute what y is into the second equation, so:
3x + 4(2x + 1) = 26
3x + 8x + 4 = 26
11x + 4 = 26
- 4
11x = 22
÷ 11
x = 2
y = (2 × 2) + 1
y = 5 + 1
y = 5
So you get x as 2 and y as 5, I hope this helps!
