Answer:
Step-by-step explanation:
the sum of angles in a triangle is 180 degrees
18 + 72 + X = 180
90 + X = 180
X = 180 -90
X = 90
the answer is in the image
subtract 7 from both sides
2x < 7- 7
subtract 7 from 7 to get 0
2x < 0
product of two numbers is < 0 if one is > 0 and the other is < 0. since 2> 0, must be < 0.
x < 0
6 and 7
we know that 42 will lie between 36 and 49
And 36=6; 49=7
so we can be sure that 42 lies between 6 and 7
