here's the right answer!
A) 76 + 80 + 78 + x = 82 times 4
234 + x = 328
x = 94
B) Mei needs a score of at least 94 on the next exam.
hope you have a good day
Answer:
Step-by-step explanation:
If the equations are true, they can be solved simultaneously.
Consider 2x-10y=-1 as Eq1 and 5x+6y=4 as Eq2
Multiplying Eq1 with 3 and Eq2 with 5 we get,
6x-30y=-3 -- Eq3 and 25x+30y=20 -- Eq4
Adding Eq3 and Eq4,
31x=17 Therefore, x=17/31
Plugin x=17/31 in Eq3,
6(17/31)-30y=-3 --- y=13/62
Plug In values of x and y in 7x-4y we get,
7(17/31)-4(13/62) = 3
So the value of 7x-4y = 3.
Answer - D.
you basically find the equation of the line first and eliminate the wrong answers...
Strategy: before u do any of this, label your coordinates as (X1,Y1) and (X2,Y2) and u can choose any of ur points to be as x1 or x2 or y1 or y1...
basically, I'll choose (6,7) as (x1,y1) and (2,-1) as (x2,y2). SO,
First you have to find the gradient (m) of the line.
you do this by using the formula m = Y2-Y1 / X2-X1 (where '/' is division sign) ....
Put the numbers in their respective places and your gradient will be 2x. we put the x after our number to represent it as a gradient as the straight line formula is y = mx+c and you've found the m.
NOW.
use the formula Y-Y1=m(x-x1) to find the equation of the line.Again u can use any Y1 and X1 here but remember your m is 2
replace the digits and solve...Hopefully you'll get sth like this if you use the points (6,7):
Y-7 = 2(x-6) ....
y=2x-12+7...
Y=2x-5! <<<< this is your straight line equation!
Now all u gotta do is rearrange all your options into y = mx+c.
D. is incorrect as it gives us y=2x+5 and not y = 2x-5 unlike the others
Hope you get it!
Answer:
x = -9
Step-by-step explanation:
1.4 - 0.2x = 3.2
0.2x = 3.2 - 1.4
0.2x= 1.8
x= -9
