Question

Help please i’m giving away 15 points math grade 7

Answer 1

Answer:

3.6

Step-by-step explanation:

$\frac{2}{3}$(6a+9)=20.4

4a+6=20.4

4a=14.4

a=3.6

Answer 2

Simplify ———
5
Equation at the end of step
1
:

2 102
(— • (6a + 9)) - ——— = 0
3 5
STEP
2
:

2
Simplify —
3
Equation at the end of step
2
:

2 102
(— • (6a + 9)) - ——— = 0
3 5
STEP
3
:

STEP
4
:
Pulling out like terms

4.1 Pull out like factors :

6a + 9 = 3 • (2a + 3)

Equation at the end of step
4
:

102
2 • (2a + 3) - ——— = 0
5
STEP
5
:
Rewriting the whole as an Equivalent Fraction

5.1 Subtracting a fraction from a whole

Rewrite the whole as a fraction using 5 as the denominator :

2 • (2a + 3) 2 • (2a + 3) • 5
2 • (2a + 3) = ———————————— = ————————————————
1 5
Equivalent fraction : The fraction thus generated looks different but has the same value as the whole

Common denominator : The equivalent fraction and the other fraction involved in the calculation share the same denominator

Adding fractions that have a common denominator :

5.2 Adding up the two equivalent fractions
Add the two equivalent fractions which now have a common denominator

Combine the numerators together, put the sum or difference over the common denominator then reduce to lowest terms if possible:

2 • (2a+3) • 5 - (102) 20a - 72
—————————————————————— = ————————
5 5
STEP
6
:

Pulling out like terms :

6.1 Pull out like factors :

20a - 72 = 4 • (5a - 18)

Equation at the end of step
6
:

4 • (5a - 18)
————————————— = 0
5
STEP
7
:

When a fraction equals zero :

7.1 When a fraction equals zero ...
Where a fraction equals zero, its numerator, the part which is above the fraction line, must equal zero.

Now,to get rid of the denominator, Tiger multiplys both sides of the equation by the denominator.

Here's how:

4•(5a-18)
————————— • 5 = 0 • 5
5
Now, on the left hand side, the 5 cancels out the denominator, while, on the right hand side, zero times anything is still zero.

The equation now takes the shape :
4 • (5a-18) = 0

Equations which are never true:

7.2 Solve : 4 = 0

This equation has no solution.
A a non-zero constant never equals zero.

Solving a Single Variable Equation:

7.3 Solve : 5a-18 = 0

Add 18 to both sides of the equation :
5a = 18
Divide both sides of the equation by 5:
a = 18/5 = 3.600

One solution was found :
a = 18/5 = 3.600

Mark me as brainliest plsssss