12=5x-13x-44
combine like terms
12 = -8x -44
add 44 to each side
12+44 = -8x
56= -8x
divide by -8 on each side
56/-8 = x
-7 =x
285.39 I belive the awsner is
Answer:
tons of high steel and
tons of low steel
Step-by-step explanation:
Let x be the number of tons of high grade steel and y be the number of tons ow low grade steel needed.
In x tons of high grade steel there are
tons of iron
tons of magnese
In y tons of low grade steel there are
tons of iron
tons of magnese
NASA orders 500 tons of steel, so

and specifies that it must be in the proportion 80% iron and 20% magnese, so

From the first equation,

Substitute it into the second equation:

His average is 86 so it is below 90. to get his average i just added all of his grades up to get 517 and then I divided 517 by 6 because thats how many grades he has and I got 86.
On the Grade row in the table it would go 83, 94, 79, 90, 96, 75 in order
The Above/Below 90 row would go -7, 4, 11, 7, -6, -3 in order
Lamont needs to get a 99 on his next test to have an average of exactly 90.
I HOPE THIS HELPED! PLEASE RATE ME AND MAKE MY ANSWER MOST BRAINLIEST!!
3 x 5 = 15 because the opposite of dividing is multiplying