Respuesta:
2x - 0.5x = 30
x = 20
Explicación paso a paso:
Llamemos "x" a la incógnita, el número desconocido.
Cuando nos referimos al doble de un número, es lo mismo que 2x.
Cuando nos referimos a la mitad de un número, es lo mismo que 0.5 x.
Consideremos que al doble de un número (2x) se le resta su mitad 0.5x) y se obtiene 30. La ecuación resultante es:
2x - 0.5x = 30
1.5x = 30
x = 30/1.5 = 20
Answer
0.045662100456621
6/131.4
One minute later at 8:01pm. One lighthouse will flash 3 times (at 20, 40 and 60 seconds)...the other will flash twice (at 30 and 60 seconds). So they will both flash 60 seconds later, at 8:01
Answer:
U = -5
Step-by-step explanation:
-8u = -7u + 5
-u = 5
u = -5
Answer:
c) 2 + 3 = 5 TRUE
d) 2 + (–3) = -1 True
Step-by-step explanation:
When adding integers (positive and negative whole numbers), there are three cases:
- Positive and positive increases and sum is positive. Ex. 4 + 6 = 10
- Positive and negative where you subtract and take the sign of the larger number. Ex. 3 + -8 = -5 or -3 + 8 = 5
- Negative and negative decrease and the sum if negative. Ex. -4 + -6 = -10.
Use these rules to simplify each expression.
a) 2 + (–3) = -1 not 1 FALSE
b) –3 + 2 = -1 not 5 FALSE
c) 2 + 3 = 5 TRUE
d) 2 + (–3) = -1 True