She can use 68 + 20 = 88 to help by noticing that the 20 is ahead of 19 by 1. She can easily mentally turn the 20 into a 19 and realized that the 88 would become 87.
The answer to the question is c
Answer:
1.true
2.false
3.false
4.true
5.true
6.false
Step-by-step explanation:
just graph it and look at it
Answer:
No solution
Step-by-step explanation:

Lets consider the equation 2.
Here we multiply the LHS and RHS with (-1).

Hence,

When we add the equations we get,

As 0 doesn't equal to -1, answer is d) No solution
Answer:
3(-x^2-6x+4)
Step-by-step explanation:
-3x^2 - 18x + 12
-3x^2 - (2 x 3^2) x + 2^2 x 3
3 (-3x^2 over 3 - 2x3^2 times x over 3 + 262 x 3 over 3)
3(-(x^2) - (2 x 3^2-1 times x) +2^2
3(-x^2 - (2 times 3x) +4)
3(-x^2-(6x) + 4)
3(-x^2 - 6x + 4)