Hello :
<span>–9.5 + 6x ≥ 42.1
6x </span>≥ 42.1 + 9.5
6x ≥ 51.6
x ≥ 51.6/6
x ≥ 8.6
using interval notation: <span>[8.6 ; +∞[ </span>
C. You'd be starting at a higher floor (positive number) and descending floors (negative number per x). If you assume x is time it's a little more logical and visual.
I'm not sure what you mean by rename
X+y=23
X-y=7.4
X+y=23
y=23-X
X-y=7.4
(23-y)-y=7.4
23-2y=7.4
-2y=-15.6
Y=7.8
X+y=23
X+7.8=23
X=15.2
Therefore the two numbers are 7.8 & 15.2
Answer:
Country A = 84
Country B = 28
Country C = 18
Step-by-step explanation:
Country A, Country B, and Country C won a total of 130 medals;
A + B + C = 130 ......1
Country B won 10 more medals than Country C;
B = C + 10 .......2
Country A won 38 more medals than the total amount won by the other two;
A = B + C + 38 ........3
Substituting equation 3 to 1;
(B+C+38) + B+C = 130
2B + 2C + 38 = 130 .......4
Substituting equation 2 into 4;
2(C+10) + 2C + 38 = 130
4C + 58 = 130
4C = 130-58 = 72
C = 72/4 = 18
B = C + 10 = 18 + 10 = 28
A = B + C + 38 = 18 + 28 + 38 = 84
Country A = 84
Country B = 28
Country C = 18