6-6a=3a-3b+1, 9a-3b=5
<span>4b - 8 =3a, 3a-4b=-8
</span>
9a-3b=5
(3a-4b=-8 )*(-3 )
9a -3b= 5
-9a+12b=+24
adding both equations
9b=29, b=29/9
3a=4b-8=4*29/9 -8=(4*29-8*9)/9 = 44/9
a=44/27
a-b=44/27 - 29/9=44/27 - 29*3/27=-43/27
this is a correct answer, unfortunately they do not have this choice, probably they made mistake somewhere. I even check the solution of equations by substitution values of a and b into equations
Answer:
Step-by-step explanation:
<u>Given</u> :
f(x) = -3/4x + 2
<u>Substitute x = 16</u> :
f(16) = -3/4(16) + 2
f(16) = -12 + 2
f(16) = -10
Answer:
30 students
Step-by-step explanation:
Yesterday: 1/3 of the 75 students (75 / 3) = 25 students
There are now 50 students remaining to give their speeches.
Today: 2/5 of the 50 students (50 / 5 = 10 x 2 ) = 20 students
50 - 20 = 30 students remaining to give their speeches.
1. −2x−4=20+6x
Step 1: Simplify both sides of the equation.
−2x−4=20+6x
−2x+−4=20+6x
−2x−4=6x+20
Step 2: Subtract 6x from both sides.
−2x−4−6x=6x+20−6x
−8x−4=20
Step 3: Add 4 to both sides.
−8x−4+4=20+4
−8x=24
Step 4: Divide both sides by -8.
−8x/−8=24/−8
x=−3
Answer:
x=−3
3. (x/4)*(4)=(9)*(4)
x=36
Answer:
x=36
4.
2(5x−1)=3x+5
Step 1: Simplify both sides of the equation.
2(5x−1)=3x+5
(2)(5x)+(2)(−1)=3x+5(Distribute)
10x+−2=3x+5
10x−2=3x+5
Step 2: Subtract 3x from both sides.
10x−2−3x=3x+5−3x
7x−2=5
Step 3: Add 2 to both sides.
7x−2+2=5+2
7x=7
Step 4: Divide both sides by 7.
7x/7=7/7
x=1
Answer:
x=1
5.
8−2(3x−4)+2x=5(x+6)+4
Step 1: Simplify both sides of the equation.
8−2(3x−4)+2x=5(x+6)+4
8+(−2)(3x)+(−2)(−4)+2x=(5)(x)+(5)(6)+4(Distribute)
8+−6x+8+2x=5x+30+4
(−6x+2x)+(8+8)=(5x)+(30+4)(Combine Like Terms)
−4x+16=5x+34
−4x+16=5x+34
Step 2: Subtract 5x from both sides.
−4x+16−5x=5x+34−5x
−9x+16=34
Step 3: Subtract 16 from both sides.
−9x+16−16=34−16
−9x=18
Step 4: Divide both sides by -9.
−9x/−9=18/−9
x=−2
Answer:
x=−2
