Answer: 490 grams of the first alloy should be used.
30 grams of the second alloy should be used.
Step-by-step explanation:
Let x represent the weight of the first alloy in grams that should be used.
Let y represent the weight of the second alloy in grams that should be used.
A chemist has two alloys, one of which is 15% gold and 20% lead. This means that the amount of gold and lead in the first alloy is
0.15x and 0.2x
The second alloy contains 30% gold and 50% lead. This means that the amount of gold and lead in the second alloy is
0.3y and 0.5y
If the alloy to be made contains 82.5 g of gold, it means that
0.15x + 0.3y = 82.5 - - - - - - - - - - - -1
The second alloy would also contain 113 g of lead. This means that
0.2x + 0.5y = 113 - - - - - - - - - - - - -2
Multiplying equation 1 by 0.2 and equation 2 by 0.15, it becomes
0.03x + 0.06y = 16.5
0.03x + 0.075y = 16.95
Subtracting, it becomes
- 0.015y = - 0.45
y = - 0.45/- 0.015
y = 30
Substituting y = 30 into equation 1, it becomes
0.15x + 0.3 × 30 = 82.5
0.15x + 9 = 82.5
0.15x = 82.5 - 9 = 73.5
x = 73.5/0.15
x = 490
Vertical angles are equal, which is similar to saying "vertical angles are congruent." Note: vertical, not verticle.
Answer: verdadero.
Step-by-step explanation:
En geometría se dice que dos figuras son semejantes si tienen la misma forma pero no necesariamente el mismo tamaño.
Ahora, lo que define la forma de un triángulo son sus ángulos, entonces si dos triángulos tienen los mismos ángulos, estos triángulos van a tener la misma forma.
Y los lados siendo proporcionales entre ellos (recordar que una relación proporcional es y = k*x) habla de la relación entre los tamaños de los dos triángulos.
Entonces si, "dos triángulos son semejantes, si sus ángulos son iguales y sus lados proporcionales" es verdadero.
Answer:
shop b
Step-by-step explanation:
We can find for example how much 100 grams of peanut butter cost in each shop using a proportion
shop A 100 : 250 = x : 325
x = (325 * 100) / 250 = $130
shop B 100 : 340 = x : 408
x = (408 * 100)/ 340 = $120
We discovered that shop B is cheaper