"Will is twice as old as Jill."
Jill's age . . . . . J
Will's age . . . . 2J .
"Three years ago . . .
Jill's age then . . . . . J - 3
Will's age then . . . . 2J - 3
". . . Jill's age then was 2/5 of Will's age then."
J - 3 = (2/5) (2J - 3)
Multiply
each side by 5 : 5J - 15 = 2 (2J - 3)
Divide
each side by 2 : 2.5 J - 7.5 = 2J - 3
Subtract 2J
from each side: 0.5 J - 7.5 = -3
Add 7.5
to each side: 0.5 J = 4.5
Multiply
each side by 2 : J = 9
Jill is 9 y.o. now.
Will is 18 y.o. now.
175 red squares out of 1000 squares = 175/1000 = 0.175 of the design is red.
Answer:
Caja de plaquetas = x = 30 €
Caja de azulejos = y = 35 €
Step-by-step explanation:
Deje que el costo de
Caja de plaquetas = x
Cuadro de mosaico = y
Por Berta
Para reformar su cocina, Berta compró la semana pasada 2 cajas de baldosas de plaquetas para el suelo y 4 cajas de baldosas para la pared por 200 €.
2x + 4y = 200 ...... Ecuación 1
Hoy
Hoy compré 2 cajas más de plaquetas y otras 2 de tejas por 130 €.
2x + 2y = 130 ..... Ecuación 2
Resolvemos usando el método de Eliminación
2x + 4y = 200 ...... Ecuación 1
2x + 2y = 130 ..... Ecuación 2
Restar la ecuación 2 de 1
2 años = 70
y = 70/2
y = 35 €
Resolviendo para x
2x + 4y = 200 ...... Ecuación 1.
2x + 4 × 35 = 200
2x + 140 = 200
2x = 200 - 140
2x = 60
x = 60/2
x = 30 €
el costo de
Caja de plaquetas = x = 30 €
Caja de azulejos = y = 35 €
8. D: The <em>longest sides of the quadrilaterals are 30 and 10</em>. That is a 30 : 10 ratio, which simplifies to <em>3 : 1, or </em>3/1. It's not 1 : 3 because it is the ratio between the large (comes first) to the small (comes second) figure.
9. B: <em>x corresponds to 26</em>, and from the previous problem, we figured out that <em>the sides of the larger figure are 3 times larger than the corresponding one on the smaller one</em>. So <em>x is 1/3 the length of 26</em>, which is 26/3.
So the answer to this equation is 9
to find the answer we first need to substitute the x for 1
so the equation would be 4×1^2+5*1
so now we simplify the equation so it would be 4+5×1
and 4+5*1 simplified is 4+5
and 4+5=9
