Answer:
80%
Step-by-step explanation:
Let's call the past exam mark m,
m*105%=84
m*105/100=84
m=84/(105/100)
m=80
Hope this helps!
Answer:
264
Step-by-step explanation:
do 20 mulitplyed by 30 then subtracted it by 336
ECH is an acute angle.
FCG is also an acute angle.
Answer:
width= 75 cm
Step-by-step explanation:
We need to recall the formula to calculate the area of a rectangle, since we are dealing with a rectangular window:
Area of rectangle = width * length
therefore, since they give us the window's area: 6525 
, and also the window's length: 87 cm, we just need to replace those values in the area formula and solve for the unknown "width". We do such by dividing both sides of the equation by 87 cm in order to isolate the unknown on one side of the equal sign;
