-2/3x -11=-7
-2/3x = 11 - 7
-2/3x = 4
x = 4 : (-2/3)
x = 4 * (-3/2)
x = 4 *(-3) : 2
x = -12 : 2
x = -6
Answer:
10%=$25.20
25%=$21.00
35%=$18.20
Step-by-step explanation:
A mark-down in price of 10% is the same as 90% of the original price. 90% can be expressed as 0.9. $28.00(0.9)=$25.20. This same explanation holds true for the 25%/35% mark-down: $28.00(1-0.25)=$21.00; $28.00(1-0.35)=$18.20. Additionally, if you try this with the 40%/50% mark-downs it doesn‘t work.
Answer:
El valor de <em>x</em> es igual a 20 o <em>x</em> = 20.
Step-by-step explanation:
Lo primero que se debe saber es que <em>dos ángulos complementarios suman un ángulo recto o 90º</em>.
Supongamos que el valor de un ángulo 
y un ángulo 
valen:
[1]
[2]
Como la suma de 
[3]
Entonces
Sumamos los factores comunes entre si:
Para la primera expresión debemos recordar que se suman sólo los coeficientes. Así:
Para despejar la incógnita <em>x</em>, debemos tener en cuenta que <em>una igualdad no se altera si se suma, se resta, se multiplica o divide un mismo valor a cada lado de ella</em>. Por esta razón, para despejar 3x, lo primero que podemos hacer es sumar -30 a cada lado de la expresión (lo que es igual a restar 30 a cada lado de la misma). Así tenemos:
Ahora dividimos cada miembro de la igualdad entre 3 (o multiplicamos cada lado de la igualdad por 
):
Como sabemos que:
Entonces:
De esta manera, el valor de <em>x</em> es igual a 20 o x = 20.
Lo anterior lo podemos comprobar considerando las ecuaciones [1], [2] y [3]. Así tenemos que:
[1]
Sustituimos x por el valor de 20:
[2]
Hacemos lo mismo para [2]:
De esta manera:
[3]
Answer:
Lyla needs 5 seed packets to have 40 flowers in her garden
Step-by-step explanation:
* Lets explain the direct proportion
- Direct proportion is the relationship between two variables when
their ratio is equal to a constant value
- If m and n are in direct proportion m ∝ n , then m = kn, where
k is constant
- We can write the direct proportion as m/n = k
* Lets solve the problem
- Lyla grew 16 flowers with 2 seed packets
- The relationship between the number of flowers and the number
of the seed packets is direct proportional
∴ F ∝ P , where F is the number of the flowers and P is the number
of the seed packets
∵ F = kP
∵ F = 16 when P = 2
∴ 16 = k(2)
- Divide both sides by 2
∴ k = 8
- Substitute the value of k in the equation
∴ F = 8P
Lets find how many packets does Lyla need to have 40 flowers
∵ F = 40
∴ 40 = 8P
- Divide both sides by 8
∴ P = 5
∴ Lyla needs 5 seed packets to have 40 flowers in her garden
