Answer:
8 ejercicios
Step-by-step explanation:
De acuerdo a la información dada, puedes plantear las siguientes ecuaciones:
x+y= 45 (1)
7x-1y= 19 (2)
x= ejercicios que resolvió bien
y= ejercicios que resolvió mal
Primero, puedes despejar x en (1):
x= 45-y (3)
Segundo, debes reemplazar (3) en (2):
7(45-y)-1y=19
315-7y-1y= 19
315-8y= 19
315-19= 8y
296= 8y
y= 296/8
y= 37
Tercero, debes reemplazar el valor de y en (3) para encontrar x:
x= 45-37
x= 8
De acuerdo a esto, la respuesta es que el hijo ha resuelto bien 8 ejercicios.
Answer:
f(9)=-22-9(9)+20=-83
Step-by-step explanation:
f(9) means x = 9, Just substitute 9 into the function.
-9(9) = -81
-22-81+20 = -83
Given :
A T.V. is measure by its diagonal.
To Find :
If the height of a 60 inch T.V. is 32 inches, what is the width.
Solution :
We know, T.V. is rectangular in shape and angle between two sides of rectangular is 90° .
Let, width of T.V. is x.
Applying Pythagoras theorem in sides, we get :

Therefore, width of T.V. is 55.42 inches.
Yes if they relate to one another using an = sign
The solution is where both lines intersect. First find the x-coordinate which we will find by going to the left two units. That means x = -2. Now going up one unit, which gives us y = 1
(-2, 1)