Answer:
X would have to equal 6. To work it out, you subtract 4 from each side to cancel out the 4. -x = -6. You have to make -x just x so you × each side by -1. You get x = 6.
Do you think than i ve understood it right
3x+9=30
3x=21
x = 21/3 = 7
x = 7
hope helped
Answer:
a. 100 mph
b. 500 mph
Step-by-step explanation:
a.
Let the speed of Lindbergh's plane be x.
Today's planes are 5 times faster, so their speed is 5x.
Today's planes speed is 400 mph faster than Lindbergh's speed.
x + 400 = 5x
5x = x + 400
4x = 400
x = 100
Lindbergh's speed was 100 mph
b. 5x = 5 * 100 = 500
Today's planes fly at 500 mph
Answer:
C
Step-by-step explanation:
7 - 2 = 5
11 - 3(2)
11 - 6 = 5
4(2) - 3
8 - 3 = 5
C is the only one that doesn't equal 5
