Y *x =20
y +x =9
rewrite 1st eq. as y = 20/x
subsituute that into 2nd eq.
20/x +x =9
multiply each term by X
20 +x^2 = 9x
subtract 9x from each side:
x^2 - 9x +20 = 0
now factor:
(x-5) (x-4) = 0
solve for x
5-5 = 0
4-4 = 0
so X can be 4 or 5
replace x into equations and solve for Y
so when X = 4, Y = 5
When X = 5, Y = 4
x= 5,4
y = 4,5
Answer:
60 degree
Step-by-step explanation:
Here all sides of this triangle are equal, which means it is an equilateral triangle.
In an equilateral triangle, all the angles are equal and are 60 degrees to satisfy angle sum property.
Divide 33 photos into 2
groups.
The ratio of the said photo is 4 : 7
Now, we have the total number of photos which is 33, so let’s add the
ratio to get the total number of ratio
=> 4 + 7 = 11
=> 33 and 11, let’s divide
=> 33 / 11 = 3, now we have the number of photos in each group.
=> 4 x 3 = 12
=> 7 x 3 = 21
Thus the ratio of photos is 12 : 21
Answer:25
Step-by-step explanation:
Proof method:
1. Calculate the length of each side, DE,DF,EF
2. Compare the length of them, if any pair of them is equal, then it's isosceles.