Answer:
x = 6/7, y = 1/2
Step-by-step explanation:
7x + 2y = 7
-14x + 2y = -11
1) 7x + 2y = 7
2y = 7 - 7x
2) -14x + 2y = -11
-14x + 7 - 7x = -11
- 21x = -11-7
- 21x = - 18
x = 18/21 = 6/7
3) 2y = 7 - 7x = 7 - 7*(6/7) = 7 - 6 = 1
2y = 1
y = 1/2
Answer:
x=√2,-√2
Step-by-step explanation:
A, it's always true
remember commutative property
a+b=b+a
a and b can be negativ numbers
so equatinos
-5.2+7.71=2.51
7.71-5.2=2.51
-8.65+3.94=-4.62
3.94-8.65=-4.62
B.
-5.2-7.71=-12.91
7.71-(-5.2)=12.91
-8.65-3.94=-12.59
3.94-(-8.65)=12.59
always false
C. when you change the order, you are subtracting a different number from a different number than before
Answer:
C) 2744 cm
Step-by-step explanation:
To find the volume of a cube you have to use this equation:
V = a^3
Now plug in the number:
V = 14^3
14^3 or 14*14*14 = 2,744
The volume is 2,744 cm
R/ r+ 15 = 3/8
Cross multiply: top of one side multiplied by bottom of other side:
R x 8 = 3 x r+ 15
Simplify:
8r = 3r + 45
Subtract 3r from both sides:
5r = 45
Divide both sides by 5:
R = 9
