Answer: ab =6
have:
=> a + b + 1 = ab
⇔ a + b + 1 - ab = 0
⇔ b - 1 - a(b - 1) + 2 = 0
⇔ (b - 1)(1 - a) = -2
because a and b are postive integers => (b - 1) and (1 - a) also are integers
=> (b - 1) ∈ {-1; 1; 2; -2;}
(1 -a) ∈ {-1; 1; 2; -2;}
because (b -1).(1-a) = -2 => we have the table:
b - 1 -1 1 2 -2
1 - a 2 -2 -1 1
a -1 3 2 0
b 0 2 3 -1
a.b 0 6 6 0
because a and b are postive integers
=> (a;b) = (3;2) or (a;b) = (2;3)
=> ab = 6
Step-by-step explanation:
Answer:
x - 231 ≤ 459
Step-by-step explanation:
Given:
Elevation ranges below sea level = 228 ft
Elevation ranges above sea level = 690 ft
Elevation = x
Computation:
Ideal range = [690-228] / 2 = 231
Tolerance range = [690+228] / 2 = 459
So,
x - 231 ≤ 459
Answer:
Step-by-step explanation:
-3 + 1/2n = 1/2 (-n + 14)
distribute
-3 + 1/2n = -1/2n + 7
-1/2n
cancel out -1/2n
-3 = n + 7
-10 = n
subtract 7
n = -10
Answer:
Ian saves 7.92
Step-by-step explanation:
9.24/6=1.54
2*9.24= 18.48
8.80/4=2.20
3*8.80= 26.40
26.0 - 18.48 = 7.92
Answer:
54 in
Step-by-step explanation:
because 6 times 5 is 30 plus 4 times 6 is 24 equals 54
