Answer:
D
Step-by-step explanation:
The rest you can elimate because of obvious inferring and reasoning so process of elimination
The answer to this question is going to be letter B
3:5=x:50
Therefore 5 ×x = 50
x = 10
Therefore 3 × 10 = 30
therefore 30 blue pens
proof = 30 blue + 50 red= 3+ 5
therefore 80 = 8x
Answer:
Select all the lines with slope
.
Step-by-step explanation:
Use the slopes to help you answer this kind of questions.
The slope of the line going through: (1, - 2) and (3,4) is given by:

We plug in the coordinates to get:

All lines that are perpendicular to this line has slope
.
Answer:
?=7
Step-by-step explanation:
Here is a cool trick that I believe only works with 9.
Add the numbers, 3+9+9+8+x= divisible by 9.
3+9+9+7+8 is 36 which is the only number divisible by 9.