Answer:
a=2 , b= (-1)
Step-by-step explanation:
8a-4b=20/×(-2)
5a-8b=62
-16a+8b= -40
5a-8b=62
now -8+8=0 right? so the only parameter that we have is a.
-16a+5a= -40+62
11a = 22/(÷11)
a=2
in order to find b, we will replace a with its value in one of the original equations (it doesn't matter which one you will choose).For instance, I chose the first one.
8×2-4b=20
-4b=20-16
-4b=4/÷(-4)
b= -1
Answer:15/31
Step-by-step explanation: because there are 31 kids in all and 15 of them are boys so 15/31
Answer:
2a^4+5a^3-6a^2+19a-20
Step-by-step explanation:
(a^2+3a-4)(2a^2-a+5)
2a^4-a^3+5a^2+6a^3-3a^2+15a-8a^2+4a-20
2a^4-a^3+6a^3+5a^2-3a^2-8a^2+15a+4a-20
2a^4+5a^3+2a^2-8a^2+19a-20
2a^4+5a^3-6a^2+19a-20
Answer:

Step-by-step explanation:
we know that
In the right triangle ABC of the figure
Applying the Pythagoras Theorem

substitute the given values

Solve for c




Answer:
210
Step-by-step explanation:
if you divide 126 by 3 you get 42 than multiply by 5 and you get 210