Answer:
Juan imprimió 7 páginas a color.
Step-by-step explanation:
Llamemos "b" a las copias en blanco y negro y "c" a las copias en color.
Juan imprimió 75 páginas. En forma simbólica es:
b + c = 75
b = 75 - c [1]
El costo de impresión de cada página en una biblioteca es de 5 centavos si es en blanco y negro o 50 centavos si es a color. En total pago $6.90. En forma simbólica es:
0.05b + 0.5c = 6.90 [2]
Si reemplazamos [1] en [2],
0.05(75-c) + 0.5c = 6.90
3.75 - 0.05c + 0.5c = 6.90
0.45c = 3.15
c = 7
Juan imprimió 7 páginas a color.
P E M D A S
Parentheses first:
So, 12 + 4 x 13 - 2
12 + 52 - 2
64 - 2
62
Answer:
25:-8&68___;+you &_356543$"&78
A. As sun peeks, it creates a straight line- sun to tree to shadow, angle=180°
b. During morning, the sun-tree-shadow changes from 180° to 90°, during noon, angle =90°.During sunset the angle changes from 90 to 0°.
c. Acute angles created in afternoon.
d. A right angle would be created at noon.
e. Obtuse angle would be created in morning.
f. Yes, a straight angle would be created at sunrise.
g. When sun is at mid-morning, the angle=45°+90°= 135°