Answer:
D. 6
Step-by-step explanation:
The system can be solved by subtracting double the second equation from the first:
... (4x +3y) -2(2x +y) = (20) -2(7)
... y = 6 . . . . . . . . . for solution (x, y) = (a, b), this tells you b=6.
Putting this into the second equation gives ...
... 2x +6 = 7
... 2x = 1
... x = 1/2
The solution is (x, y) = (a, b) = (1/2, 6). b = 6.
Answer:
5-(-7)=5+7
Step-by-step explanation:
keep in mind that two negatives make a positive. therefore it would be 5+7=5+7. i hope this helps :)
B and c are brothers
b=7+x
c=x-7
bc=95
a.
(x+7)(x-7)=95
b.
x^2-49=95
add 49 to both sides
x^2=144
sqrt both sides
x=12
tina=12
Answer:
C
Step-by-step explanation:
Te unoccupied volume (V) of the cube is calculated as
V = volume of cube - volume of sphere
= 7³ - πr³ ( r is the radius and r = 7 ÷ 2 = 3.5 )
= 343 - π × 3,5³
= 343 - π × 42.875
= 343 - 179.59438
= 163.4....
≈ 160 cm³ ( to the nearest 10 cm³ )