X²+10x+21=0
/\ = 10²-4*1*21
/\ = 100 - 84
/\ = 16
x = (-10+/-\/16)/2
x = (-10+/-4)/2
x' = (-10+4)/2 = -6/2 = -3
x" = (-10-4)/2 = -14/2 = -7
S: {-3; -7}
Answer:
5 cm
Step-by-step explanation:
32 / 4 = 8
40 / 8 = x
40 / 8 = 5
32 and 4 are corresponding, and 40 and x are as well. Find the relation between 32 and 4, then apply it to 40 to find the value of x.
Set up a proportion
3 coins:8 notes and then the other one 24 coins : x (unknown notes)
they have a relationship so we can set them equal to each other.
3/8=24/x cross multiply: 8 * 24 = 192
Now divide that by 3: 192/3 = 64
So there are 64 notes in the bag
Answer:
D. please mark me brainliest
Step-by-step explanation:
So thie equation basically means 2 times a number and 4 times 2 and the sum of that so as a equation it is 2*n+8 so it is n+4 times 2 so twice the sum of a number and 4
Answer:
60
Step-by-step explanation:
if 3 represents 5% and we know 5%*20 =100% then
3*20=60 represents 100%