Solve the equation and check your solutions

Answer:
[10.a=11] [12.n=25÷4] [13.h=1]
Step-by-step explanation:
10.[a-9]=20
a=20-9
a=11
12.-5[2n-6]+7=-23
23-5+7=[2n-6]
25=4n [÷4]
n=25÷4
13.[h-5]=3h-7
h-3h=5-7
-2h=-2 [÷[-2]]
h=1
sorry i could not do 11.
Answer:
10) a = 29 and a = -11
11) No solutions
12) n = 6 and n = 0
13) h = 3
Step-by-step explanation:
The absolute value of a number is its positive numerical value.
To solve an equation containing an absolute value:
[tex]|a-9|=20[/tex]
[tex]\begin{aligned}\underline{\text{Case 1}} & & \underline{\text{Case 2}}\\a-9 & = 20 & \quad \quad a - 9 & = -20\\a & = 29 & a & = -11\end{aligned}[/tex]
Check
[tex]\implies |29-9|=|20|=20[/tex]
[tex]\implies |-11-9|=|-20|=20[/tex]
Therefore, the solutions are:
[tex]\begin{aligned} |3b+b+1|+8 & =0\\\implies |4b+1|+8 & = 0\\|4b+1| &=-8\end{aligned}[/tex]
Cannot be solved as an absolute value is always positive.
[tex]\begin{aligned}-5|2n-6|+7 & =-23 \\\implies -5|2n-6| & = -30\\|2n-6| & = 6\end{aligned}[/tex]
[tex]\begin{aligned}\underline{\text{Case 1}} & & \underline{\text{Case 2}}\\2n-6 & = 6 & \quad \quad 2n-6 & = -6\\2n & = 12 & 2n & = 0\\n & = 6 & n & = 0\end{aligned}[/tex]
Check
[tex]\begin{aligned} \implies -5|2(6)-6|+7 & =-5|6|+7\\ &=-5(6)+7 \\ & =-30+7 \\ & =-23 \end{aligned}[/tex]
[tex]\begin{aligned} \implies -5|2(0)-6|+7 & =-5|-6|+7 \\ & =-5(6)+7 \\ & =-30+7\\ & =-23 \end{aligned}[/tex]
Therefore, the solutions are:
[tex]|h-5|=3h-7[/tex]
[tex]\begin{aligned}\underline{\text{Case 1}} & & \underline{\text{Case 2}}\\h-5 & = 3h-7 & \quad \quad h-5 & = -(3h-7)\\h+2 & = 3h & h-5 & = -3h+7\\2 & = 2h & h-12 & = -3h\\h & = 1 & -12 & = -4h\\ & & h & = 3\end{aligned}[/tex]
[tex]\begin{aligned}\implies |h-5| & =3h-7\\|1-5| & = 3(1)-7\\|-4| & = 3-7\\4 & = -4\end{aligned}[/tex]
[tex]\begin{aligned}\implies |h-5| & =3h-7\\|1-3| & = 3(3)-7\\|-2| & = 9-7\\2 & = 2\end{aligned}[/tex]
Therefore, the only valid solution is h = 3.
Learn more about absolute values here:
https://brainly.com/question/28248735