4x+5x = 90
9x = 90
x = 10
10y + 10 + 5x = 180
10y + 10 +5(10) = 180
10y + 60 = 180
10y = 120
y = 12
answer
<span>d) x = 10, y = 12</span>
Answer:
Add 4 to each side
Step-by-step explanation:
Answer:
a) $654
b) 27 unidades cuadradas
c) 721
Step-by-step explanation:
a) ¿Cuál es el valor de un bolígrafo cuando la docena se compra por $ 7848?
Una docena = 12
Por eso:
12 bolígrafos = $ 7848
1 bolígrafo = $ x
Cruz multiplicar
12 bolígrafos × $ x = 1 bolígrafo × $ 7848
$ x = 1 bolígrafo × $ 7848/12
$ x = $654
b) Área de un triángulo ¿9 unidades de base y 6 unidades de altura?
Área de un triángulo =
= 1/2 × Base × Altura
1/2 × 9 × 6
= 27 unidades cuadradas
c) Cien veces la suma de 4.5 con 2.71
Esto se calcula como:
100 × (4,5 + 2,71)
= 100 × (7.21)
= 721
Answer:
Sam's thinking was incorrect.
On number first we have to move 10 units from 0 in positive direction after that negative sign means move in left direction.
But we have 2 negative signs so we need to move 6 units more on positive or right direct as shown below.
Step-by-step explanation:
Answer:
-1
Step-by-step explanation:
The expression evaluates to the indeterminate form -∞/∞, so L'Hopital's rule is appropriately applied. We assume this is the common log.
d(log(x))/dx = 1/(x·ln(10))
d(log(cot(x)))/dx = 1/(cot(x)·ln(10)·(-csc²(x)) = -1/(sin(x)·cos(x)·ln(10))
Then the ratio of these derivatives is ...
lim = -sin(x)cos(x)·ln(10)/(x·ln(10)) = -sin(x)cos(x)/x
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At x=0, this has the indeterminate form 0/0, so L'Hopital's rule can be applied again.
d(-sin(x)cos(x))/dx = -cos(2x)
dx/dx = 1
so the limit is ...
lim = -cos(2x)/1
lim = -1 when evaluated at x=0.
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I find it useful to use a graphing calculator to give an estimate of the limit of an indeterminate form.